Merge pull request #121 from foogod/ds18b20-updates
DS18B20 API Improvements
This commit is contained in:
Angus Gratton
commit
83c5f91bc0
6 changed files with 830 additions and 483 deletions
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@ -19,15 +19,14 @@
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// DS18B20 driver
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#include "ds18b20/ds18b20.h"
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// Onewire init
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#include "onewire/onewire.h"
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void broadcast_temperature(void *pvParameters)
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{
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uint8_t amount = 0;
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uint8_t sensors = 2;
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ds_sensor_t t[sensors];
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uint8_t sensors = 1;
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ds18b20_addr_t addrs[sensors];
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float results[sensors];
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// Use GPIO 13 as one wire pin.
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uint8_t GPIO_FOR_ONE_WIRE = 13;
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@ -36,8 +35,6 @@ void broadcast_temperature(void *pvParameters)
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// Broadcaster part
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err_t err;
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// Initialize one wire bus.
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onewire_init(GPIO_FOR_ONE_WIRE);
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while(1) {
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@ -66,18 +63,17 @@ void broadcast_temperature(void *pvParameters)
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for(;;) {
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// Search all DS18B20, return its amount and feed 't' structure with result data.
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amount = ds18b20_read_all(GPIO_FOR_ONE_WIRE, t);
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amount = ds18b20_scan_devices(GPIO_FOR_ONE_WIRE, addrs, sensors);
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if (amount < sensors){
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printf("Something is wrong, I expect to see %d sensors \nbut just %d was detected!\n", sensors, amount);
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}
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for (int i = 0; i < amount; ++i)
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ds18b20_measure_and_read_multi(GPIO_FOR_ONE_WIRE, addrs, sensors, results);
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for (int i = 0; i < sensors; ++i)
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{
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int intpart = (int)t[i].value;
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int fraction = (int)((t[i].value - intpart) * 100);
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// Multiple "" here is just to satisfy compiler and don`t raise 'hex escape sequence out of range' warning.
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sprintf(msg, "Sensor %d report: %d.%02d ""\xC2""\xB0""C\n",t[i].id, intpart, fraction);
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// ("\xC2\xB0" is the degree character (U+00B0) in UTF-8)
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sprintf(msg, "Sensor %08x%08x reports: %f \xC2\xB0""C\n", (uint32_t)(addrs[i] >> 32), (uint32_t)addrs[i], results[i]);
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printf("%s", msg);
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struct netbuf* buf = netbuf_new();
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@ -1,59 +1,78 @@
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/* ds18b20 - Retrieves temperature from ds18b20 sensors and print it out.
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/* ds18b20_onewire.c - Retrieves readings from one or more DS18B20 temperature
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* sensors, and prints the results to stdout.
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*
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* This sample code is in the public domain.,
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*/
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#include "espressif/esp_common.h"
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#include "esp/uart.h"
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#include "FreeRTOS.h"
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#include "task.h"
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#include "timers.h"
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#include "queue.h"
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#include "esp/uart.h"
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// DS18B20 driver
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#include "ds18b20/ds18b20.h"
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// Onewire init
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#include "onewire/onewire.h"
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void print_temperature(void *pvParameters)
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{
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int delay = 500;
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uint8_t amount = 0;
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// Declare amount of sensors
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uint8_t sensors = 2;
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ds_sensor_t t[sensors];
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#define SENSOR_GPIO 13
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#define MAX_SENSORS 8
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#define RESCAN_INTERVAL 8
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#define LOOP_DELAY_MS 250
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// Use GPIO 13 as one wire pin.
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uint8_t GPIO_FOR_ONE_WIRE = 13;
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void print_temperature(void *pvParameters) {
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ds18b20_addr_t addrs[MAX_SENSORS];
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float temps[MAX_SENSORS];
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int sensor_count;
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onewire_init(GPIO_FOR_ONE_WIRE);
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// There is no special initialization required before using the ds18b20
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// routines. However, we make sure that the internal pull-up resistor is
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// enabled on the GPIO pin so that one can connect up a sensor without
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// needing an external pull-up (Note: The internal (~47k) pull-ups of the
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// ESP8266 do appear to work, at least for simple setups (one or two sensors
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// connected with short leads), but do not technically meet the pull-up
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// requirements from the DS18B20 datasheet and may not always be reliable.
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// For a real application, a proper 4.7k external pull-up resistor is
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// recommended instead!)
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gpio_set_pullup(SENSOR_GPIO, true, true);
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while(1) {
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// Search all DS18B20, return its amount and feed 't' structure with result data.
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amount = ds18b20_read_all(GPIO_FOR_ONE_WIRE, t);
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// Every RESCAN_INTERVAL samples, check to see if the sensors connected
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// to our bus have changed.
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sensor_count = ds18b20_scan_devices(SENSOR_GPIO, addrs, MAX_SENSORS);
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if (amount < sensors){
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printf("Something is wrong, I expect to see %d sensors \nbut just %d was detected!\n", sensors, amount);
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}
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if (sensor_count < 1) {
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printf("\nNo sensors detected!\n");
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} else {
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printf("\n%d sensors detected:\n", sensor_count);
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// If there were more sensors found than we have space to handle,
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// just report the first MAX_SENSORS..
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if (sensor_count > MAX_SENSORS) sensor_count = MAX_SENSORS;
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for (int i = 0; i < amount; ++i)
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{
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int intpart = (int)t[i].value;
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int fraction = (int)((t[i].value - intpart) * 100);
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// Multiple "" here is just to satisfy compiler and don`t raise 'hex escape sequence out of range' warning.
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printf("Sensor %d report: %d.%02d ""\xC2""\xB0""C\n",t[i].id, intpart, fraction);
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// Do a number of temperature samples, and print the results.
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for (int i = 0; i < RESCAN_INTERVAL; i++) {
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ds18b20_measure_and_read_multi(SENSOR_GPIO, addrs, sensor_count, temps);
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for (int j = 0; j < sensor_count; j++) {
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// The DS18B20 address is a 64-bit integer, but newlib-nano
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// printf does not support printing 64-bit values, so we
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// split it up into two 32-bit integers and print them
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// back-to-back to make it look like one big hex number.
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uint32_t addr0 = addrs[j] >> 32;
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uint32_t addr1 = addrs[j];
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float temp_c = temps[j];
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float temp_f = (temp_c * 1.8) + 32;
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printf(" Sensor %08x%08x reports %f deg C (%f deg F)\n", addr0, addr1, temp_c, temp_f);
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}
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printf("\n");
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vTaskDelay(delay / portTICK_RATE_MS);
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// Wait for a little bit between each sample (note that the
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// ds18b20_measure_and_read_multi operation already takes at
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// least 750ms to run, so this is on top of that delay).
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vTaskDelay(LOOP_DELAY_MS / portTICK_RATE_MS);
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}
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}
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}
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}
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void user_init(void)
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{
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void user_init(void) {
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uart_set_baud(0, 115200);
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printf("SDK version:%s\n", sdk_system_get_sdk_version());
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xTaskCreate(&print_temperature, (signed char *)"print_temperature", 256, NULL, 2, NULL);
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}
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@ -1,43 +1,47 @@
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#include "FreeRTOS.h"
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#include "task.h"
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#include "math.h"
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#include "onewire/onewire.h"
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#include "ds18b20.h"
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#define DS1820_WRITE_SCRATCHPAD 0x4E
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#define DS1820_READ_SCRATCHPAD 0xBE
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#define DS1820_COPY_SCRATCHPAD 0x48
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#define DS1820_READ_EEPROM 0xB8
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#define DS1820_READ_PWRSUPPLY 0xB4
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#define DS1820_SEARCHROM 0xF0
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#define DS1820_SKIP_ROM 0xCC
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#define DS1820_READROM 0x33
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#define DS1820_MATCHROM 0x55
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#define DS1820_ALARMSEARCH 0xEC
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#define DS1820_CONVERT_T 0x44
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#define DS18B20_WRITE_SCRATCHPAD 0x4E
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#define DS18B20_READ_SCRATCHPAD 0xBE
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#define DS18B20_COPY_SCRATCHPAD 0x48
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#define DS18B20_READ_EEPROM 0xB8
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#define DS18B20_READ_PWRSUPPLY 0xB4
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#define DS18B20_SEARCHROM 0xF0
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#define DS18B20_SKIP_ROM 0xCC
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#define DS18B20_READROM 0x33
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#define DS18B20_MATCHROM 0x55
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#define DS18B20_ALARMSEARCH 0xEC
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#define DS18B20_CONVERT_T 0x44
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#define os_sleep_ms(x) vTaskDelay(((x) + portTICK_RATE_MS - 1) / portTICK_RATE_MS)
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uint8_t ds18b20_read_all(uint8_t pin, ds_sensor_t *result) {
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uint8_t addr[8];
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onewire_addr_t addr;
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onewire_search_t search;
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uint8_t sensor_id = 0;
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onewire_reset_search(pin);
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while(onewire_search(pin, addr)){
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uint8_t crc = onewire_crc8(addr, 7);
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if (crc != addr[7]){
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printf("CRC check failed: %02X %02X\n", addr[7], crc);
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onewire_search_start(&search);
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while ((addr = onewire_search_next(&search, pin)) != ONEWIRE_NONE) {
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uint8_t crc = onewire_crc8((uint8_t *)&addr, 7);
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if (crc != (addr >> 56)){
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printf("CRC check failed: %02X %02X\n", (unsigned)(addr >> 56), crc);
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return 0;
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}
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onewire_reset(pin);
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onewire_select(pin, addr);
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onewire_write(pin, DS1820_CONVERT_T, ONEWIRE_DEFAULT_POWER);
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onewire_write(pin, DS18B20_CONVERT_T);
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onewire_power(pin);
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vTaskDelay(750 / portTICK_RATE_MS);
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onewire_reset(pin);
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onewire_select(pin, addr);
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onewire_write(pin, DS1820_READ_SCRATCHPAD, ONEWIRE_DEFAULT_POWER);
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onewire_write(pin, DS18B20_READ_SCRATCHPAD);
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uint8_t get[10];
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@ -71,15 +75,15 @@ uint8_t ds18b20_read_all(uint8_t pin, ds_sensor_t *result) {
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float ds18b20_read_single(uint8_t pin) {
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onewire_reset(pin);
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onewire_skip_rom(pin);
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onewire_write(pin, DS18B20_CONVERT_T);
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onewire_write(pin, DS1820_SKIP_ROM, ONEWIRE_DEFAULT_POWER);
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onewire_write(pin, DS1820_CONVERT_T, ONEWIRE_DEFAULT_POWER);
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onewire_power(pin);
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vTaskDelay(750 / portTICK_RATE_MS);
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onewire_reset(pin);
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onewire_write(pin, DS1820_SKIP_ROM, ONEWIRE_DEFAULT_POWER);
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onewire_write(pin, DS1820_READ_SCRATCHPAD, ONEWIRE_DEFAULT_POWER);
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onewire_skip_rom(pin);
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onewire_write(pin, DS18B20_READ_SCRATCHPAD);
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uint8_t get[10];
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@ -106,3 +110,114 @@ float ds18b20_read_single(uint8_t pin) {
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return temperature;
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//printf("Got a DS18B20 Reading: %d.%02d\n", (int)temperature, (int)(temperature - (int)temperature) * 100);
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}
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bool ds18b20_measure(int pin, ds18b20_addr_t addr, bool wait) {
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if (!onewire_reset(pin)) {
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return false;
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}
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if (addr == DS18B20_ANY) {
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onewire_skip_rom(pin);
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} else {
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onewire_select(pin, addr);
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}
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taskENTER_CRITICAL();
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onewire_write(pin, DS18B20_CONVERT_T);
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// For parasitic devices, power must be applied within 10us after issuing
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// the convert command.
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onewire_power(pin);
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taskEXIT_CRITICAL();
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if (wait) {
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os_sleep_ms(750);
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onewire_depower(pin);
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}
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return true;
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}
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bool ds18b20_read_scratchpad(int pin, ds18b20_addr_t addr, uint8_t *buffer) {
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uint8_t crc;
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uint8_t expected_crc;
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if (!onewire_reset(pin)) {
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return false;
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}
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if (addr == DS18B20_ANY) {
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onewire_skip_rom(pin);
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} else {
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onewire_select(pin, addr);
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}
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onewire_write(pin, DS18B20_READ_SCRATCHPAD);
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for (int i = 0; i < 8; i++) {
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buffer[i] = onewire_read(pin);
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}
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crc = onewire_read(pin);
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expected_crc = onewire_crc8(buffer, 8);
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if (crc != expected_crc) {
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printf("CRC check failed reading scratchpad: %02x %02x %02x %02x %02x %02x %02x %02x : %02x (expected %02x)\n", buffer[0], buffer[1], buffer[2], buffer[3], buffer[4], buffer[5], buffer[6], buffer[7], crc, expected_crc);
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return false;
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}
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return true;
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}
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float ds18b20_read_temperature(int pin, ds18b20_addr_t addr) {
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uint8_t scratchpad[8];
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int temp;
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if (!ds18b20_read_scratchpad(pin, addr, scratchpad)) {
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return NAN;
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}
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temp = scratchpad[1] << 8 | scratchpad[0];
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return ((float)temp * 625.0)/10000;
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}
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float ds18b20_measure_and_read(int pin, ds18b20_addr_t addr) {
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if (!ds18b20_measure(pin, addr, true)) {
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return NAN;
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}
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return ds18b20_read_temperature(pin, addr);
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}
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bool ds18b20_measure_and_read_multi(int pin, ds18b20_addr_t *addr_list, int addr_count, float *result_list) {
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if (!ds18b20_measure(pin, DS18B20_ANY, true)) {
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for (int i=0; i < addr_count; i++) {
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result_list[i] = NAN;
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}
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return false;
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}
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return ds18b20_read_temp_multi(pin, addr_list, addr_count, result_list);
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}
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int ds18b20_scan_devices(int pin, ds18b20_addr_t *addr_list, int addr_count) {
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onewire_search_t search;
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onewire_addr_t addr;
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int found = 0;
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onewire_search_start(&search);
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while ((addr = onewire_search_next(&search, pin)) != ONEWIRE_NONE) {
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if (found < addr_count) {
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addr_list[found] = addr;
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}
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found++;
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}
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return found;
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}
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bool ds18b20_read_temp_multi(int pin, ds18b20_addr_t *addr_list, int addr_count, float *result_list) {
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bool result = true;
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for (int i = 0; i < addr_count; i++) {
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result_list[i] = ds18b20_read_temperature(pin, addr_list[i]);
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if (isnan(result_list[i])) {
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result = false;
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}
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}
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return result;
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}
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@ -1,6 +1,139 @@
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#ifndef DRIVER_DS18B20_H_
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#define DRIVER_DS18B20_H_
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#include "onewire/onewire.h"
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/** @file ds18b20.h
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*
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* Communicate with the DS18B20 family of one-wire temperature sensor ICs.
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*
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*/
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typedef onewire_addr_t ds18b20_addr_t;
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/** An address value which can be used to indicate "any device on the bus" */
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#define DS18B20_ANY ONEWIRE_NONE
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/** Find the addresses of all DS18B20 devices on the bus.
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*
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* Scans the bus for all devices and places their addresses in the supplied
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* array. If there are more than `addr_count` devices on the bus, only the
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* first `addr_count` are recorded.
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*
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* @param pin The GPIO pin connected to the DS18B20 bus
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* @param addr_list A pointer to an array of ds18b20_addr_t values. This
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* will be populated with the addresses of the found
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* devices.
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* @param addr_count Number of slots in the `addr_list` array. At most this
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* many addresses will be returned.
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*
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* @returns The number of devices found. Note that this may be less than,
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* equal to, or more than `addr_count`, depending on how many DS18B20 devices
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* are attached to the bus.
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*/
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int ds18b20_scan_devices(int pin, ds18b20_addr_t *addr_list, int addr_count);
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/** Tell one or more sensors to perform a temperature measurement and
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* conversion (CONVERT_T) operation. This operation can take up to 750ms to
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* complete.
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*
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* If `wait=true`, this routine will automatically drive the pin high for the
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* necessary 750ms after issuing the command to ensure parasitically-powered
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* devices have enough power to perform the conversion operation (for
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* non-parasitically-powered devices, this is not necessary but does not
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* hurt). If `wait=false`, this routine will drive the pin high, but will
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* then return immediately. It is up to the caller to wait the requisite time
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* and then depower the bus using onewire_depower() or by issuing another
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* command once conversion is done.
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*
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* @param pin The GPIO pin connected to the DS18B20 device
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* @param addr The 64-bit address of the device on the bus. This can be set
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* to ::DS18B20_ANY to send the command to all devices on the bus
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* at the same time.
|
||||
* @param wait Whether to wait for the necessary 750ms for the DS18B20 to
|
||||
* finish performing the conversion before returning to the
|
||||
* caller (You will normally want to do this).
|
||||
*
|
||||
* @returns `true` if the command was successfully issued, or `false` on error.
|
||||
*/
|
||||
bool ds18b20_measure(int pin, ds18b20_addr_t addr, bool wait);
|
||||
|
||||
/** Read the value from the last CONVERT_T operation.
|
||||
*
|
||||
* This should be called after ds18b20_measure() to fetch the result of the
|
||||
* temperature measurement.
|
||||
*
|
||||
* @param pin The GPIO pin connected to the DS18B20 device
|
||||
* @param addr The 64-bit address of the device to read. This can be set
|
||||
* to ::DS18B20_ANY to read any device on the bus (but note
|
||||
* that this will only work if there is exactly one device
|
||||
* connected, or they will corrupt each others' transmissions)
|
||||
*
|
||||
* @returns The temperature in degrees Celsius, or NaN if there was an error.
|
||||
*/
|
||||
float ds18b20_read_temperature(int pin, ds18b20_addr_t addr);
|
||||
|
||||
/** Read the value from the last CONVERT_T operation for multiple devices.
|
||||
*
|
||||
* This should be called after ds18b20_measure() to fetch the result of the
|
||||
* temperature measurement.
|
||||
*
|
||||
* @param pin The GPIO pin connected to the DS18B20 bus
|
||||
* @param addr_list A list of addresses for devices to read.
|
||||
* @param addr_count The number of entries in `addr_list`.
|
||||
* @param result_list An array of floats to hold the returned temperature
|
||||
* values. It should have at least `addr_count` entries.
|
||||
*
|
||||
* @returns `true` if all temperatures were fetched successfully, or `false`
|
||||
* if one or more had errors (the temperature for erroring devices will be
|
||||
* returned as NaN).
|
||||
*/
|
||||
bool ds18b20_read_temp_multi(int pin, ds18b20_addr_t *addr_list, int addr_count, float *result_list);
|
||||
|
||||
/** Perform a ds18b20_measure() followed by ds18b20_read_temperature()
|
||||
*
|
||||
* @param pin The GPIO pin connected to the DS18B20 device
|
||||
* @param addr The 64-bit address of the device to read. This can be set
|
||||
* to ::DS18B20_ANY to read any device on the bus (but note
|
||||
* that this will only work if there is exactly one device
|
||||
* connected, or they will corrupt each others' transmissions)
|
||||
*
|
||||
* @returns The temperature in degrees Celsius, or NaN if there was an error.
|
||||
*/
|
||||
float ds18b20_measure_and_read(int pin, ds18b20_addr_t addr);
|
||||
|
||||
/** Perform a ds18b20_measure() followed by ds18b20_read_temp_multi()
|
||||
*
|
||||
* @param pin The GPIO pin connected to the DS18B20 bus
|
||||
* @param addr_list A list of addresses for devices to read.
|
||||
* @param addr_count The number of entries in `addr_list`.
|
||||
* @param result_list An array of floats to hold the returned temperature
|
||||
* values. It should have at least `addr_count` entries.
|
||||
*
|
||||
* @returns `true` if all temperatures were fetched successfully, or `false`
|
||||
* if one or more had errors (the temperature for erroring devices will be
|
||||
* returned as NaN).
|
||||
*/
|
||||
bool ds18b20_measure_and_read_multi(int pin, ds18b20_addr_t *addr_list, int addr_count, float *result_list);
|
||||
|
||||
/** Read the scratchpad data for a particular DS18B20 device.
|
||||
*
|
||||
* This is not generally necessary to do directly. It is done automatically
|
||||
* as part of ds18b20_read_temperature().
|
||||
*
|
||||
* @param pin The GPIO pin connected to the DS18B20 device
|
||||
* @param addr The 64-bit address of the device to read. This can be set
|
||||
* to ::DS18B20_ANY to read any device on the bus (but note
|
||||
* that this will only work if there is exactly one device
|
||||
* connected, or they will corrupt each others' transmissions)
|
||||
* @param buffer An 8-byte buffer to hold the read data.
|
||||
*
|
||||
* @returns `true` if the data was read successfully, or `false` on error.
|
||||
*/
|
||||
bool ds18b20_read_scratchpad(int pin, ds18b20_addr_t addr, uint8_t *buffer);
|
||||
|
||||
// The following are obsolete/deprecated APIs
|
||||
|
||||
typedef struct {
|
||||
uint8_t id;
|
||||
float value;
|
||||
|
|
|
|||
|
|
@ -1,206 +1,207 @@
|
|||
#include "onewire.h"
|
||||
#include "string.h"
|
||||
#include "task.h"
|
||||
#include "esp/gpio.h"
|
||||
|
||||
// global search state
|
||||
static unsigned char ROM_NO[ONEWIRE_NUM][8];
|
||||
static uint8_t LastDiscrepancy[ONEWIRE_NUM];
|
||||
static uint8_t LastFamilyDiscrepancy[ONEWIRE_NUM];
|
||||
static uint8_t LastDeviceFlag[ONEWIRE_NUM];
|
||||
#define ONEWIRE_SELECT_ROM 0x55
|
||||
#define ONEWIRE_SKIP_ROM 0xcc
|
||||
#define ONEWIRE_SEARCH 0xf0
|
||||
|
||||
void onewire_init(uint8_t pin)
|
||||
{
|
||||
gpio_enable(pin, GPIO_INPUT);
|
||||
onewire_reset_search(pin);
|
||||
// Waits up to `max_wait` microseconds for the specified pin to go high.
|
||||
// Returns true if successful, false if the bus never comes high (likely
|
||||
// shorted).
|
||||
static inline bool _onewire_wait_for_bus(int pin, int max_wait) {
|
||||
bool state;
|
||||
for (int i = 0; i < ((max_wait + 4) / 5); i++) {
|
||||
if (gpio_read(pin)) break;
|
||||
sdk_os_delay_us(5);
|
||||
}
|
||||
state = gpio_read(pin);
|
||||
// Wait an extra 1us to make sure the devices have an adequate recovery
|
||||
// time before we drive things low again.
|
||||
sdk_os_delay_us(1);
|
||||
return state;
|
||||
}
|
||||
|
||||
// Perform the onewire reset function. We will wait up to 250uS for
|
||||
// the bus to come high, if it doesn't then it is broken or shorted
|
||||
// and we return a 0;
|
||||
// and we return false;
|
||||
//
|
||||
// Returns 1 if a device asserted a presence pulse, 0 otherwise.
|
||||
// Returns true if a device asserted a presence pulse, false otherwise.
|
||||
//
|
||||
uint8_t onewire_reset(uint8_t pin)
|
||||
{
|
||||
uint8_t r;
|
||||
uint8_t retries = 125;
|
||||
bool onewire_reset(int pin) {
|
||||
bool r;
|
||||
|
||||
noInterrupts();
|
||||
DIRECT_MODE_INPUT(pin);
|
||||
interrupts();
|
||||
gpio_enable(pin, GPIO_OUT_OPEN_DRAIN);
|
||||
gpio_write(pin, 1);
|
||||
// wait until the wire is high... just in case
|
||||
do {
|
||||
if (--retries == 0) return 0;
|
||||
delayMicroseconds(2);
|
||||
} while ( !DIRECT_READ(pin));
|
||||
if (!_onewire_wait_for_bus(pin, 250)) return false;
|
||||
|
||||
gpio_write(pin, 0);
|
||||
sdk_os_delay_us(480);
|
||||
|
||||
taskENTER_CRITICAL();
|
||||
gpio_write(pin, 1); // allow it to float
|
||||
sdk_os_delay_us(70);
|
||||
r = !gpio_read(pin);
|
||||
taskEXIT_CRITICAL();
|
||||
|
||||
// Wait for all devices to finish pulling the bus low before returning
|
||||
if (!_onewire_wait_for_bus(pin, 410)) return false;
|
||||
|
||||
noInterrupts();
|
||||
DIRECT_WRITE_LOW(pin);
|
||||
DIRECT_MODE_OUTPUT(pin); // drive output low
|
||||
interrupts();
|
||||
delayMicroseconds(480);
|
||||
noInterrupts();
|
||||
DIRECT_MODE_INPUT(pin); // allow it to float
|
||||
delayMicroseconds(70);
|
||||
r = !DIRECT_READ(pin);
|
||||
interrupts();
|
||||
delayMicroseconds(410);
|
||||
return r;
|
||||
}
|
||||
|
||||
// Write a bit. Port and bit is used to cut lookup time and provide
|
||||
// more certain timing.
|
||||
//
|
||||
static void onewire_write_bit(uint8_t pin, uint8_t v)
|
||||
{
|
||||
if (v & 1) {
|
||||
noInterrupts();
|
||||
DIRECT_WRITE_LOW(pin);
|
||||
DIRECT_MODE_OUTPUT(pin); // drive output low
|
||||
delayMicroseconds(10);
|
||||
DIRECT_WRITE_HIGH(pin); // drive output high
|
||||
interrupts();
|
||||
delayMicroseconds(55);
|
||||
static bool _onewire_write_bit(int pin, bool v) {
|
||||
if (!_onewire_wait_for_bus(pin, 10)) return false;
|
||||
if (v) {
|
||||
taskENTER_CRITICAL();
|
||||
gpio_write(pin, 0); // drive output low
|
||||
sdk_os_delay_us(10);
|
||||
gpio_write(pin, 1); // allow output high
|
||||
taskEXIT_CRITICAL();
|
||||
sdk_os_delay_us(55);
|
||||
} else {
|
||||
noInterrupts();
|
||||
DIRECT_WRITE_LOW(pin);
|
||||
DIRECT_MODE_OUTPUT(pin); // drive output low
|
||||
delayMicroseconds(65);
|
||||
DIRECT_WRITE_HIGH(pin); // drive output high
|
||||
interrupts();
|
||||
delayMicroseconds(5);
|
||||
taskENTER_CRITICAL();
|
||||
gpio_write(pin, 0); // drive output low
|
||||
sdk_os_delay_us(65);
|
||||
gpio_write(pin, 1); // allow output high
|
||||
taskEXIT_CRITICAL();
|
||||
}
|
||||
sdk_os_delay_us(1);
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
// Read a bit. Port and bit is used to cut lookup time and provide
|
||||
// more certain timing.
|
||||
//
|
||||
static uint8_t onewire_read_bit(uint8_t pin)
|
||||
{
|
||||
uint8_t r;
|
||||
static int _onewire_read_bit(int pin) {
|
||||
int r;
|
||||
|
||||
if (!_onewire_wait_for_bus(pin, 10)) return -1;
|
||||
taskENTER_CRITICAL();
|
||||
gpio_write(pin, 0);
|
||||
sdk_os_delay_us(2);
|
||||
gpio_write(pin, 1); // let pin float, pull up will raise
|
||||
sdk_os_delay_us(11);
|
||||
r = gpio_read(pin); // Must sample within 15us of start
|
||||
taskEXIT_CRITICAL();
|
||||
sdk_os_delay_us(48);
|
||||
|
||||
noInterrupts();
|
||||
DIRECT_MODE_OUTPUT(pin);
|
||||
DIRECT_WRITE_LOW(pin);
|
||||
delayMicroseconds(3);
|
||||
DIRECT_MODE_INPUT(pin); // let pin float, pull up will raise
|
||||
delayMicroseconds(10);
|
||||
r = DIRECT_READ(pin);
|
||||
interrupts();
|
||||
delayMicroseconds(53);
|
||||
return r;
|
||||
}
|
||||
|
||||
// Write a byte. The writing code uses the active drivers to raise the
|
||||
// pin high, if you need power after the write (e.g. DS18S20 in
|
||||
// parasite power mode) then set 'power' to 1, otherwise the pin will
|
||||
// go tri-state at the end of the write to avoid heating in a short or
|
||||
// other mishap.
|
||||
// Write a byte. The writing code uses open-drain mode and expects the pullup
|
||||
// resistor to pull the line high when not driven low. If you need strong
|
||||
// power after the write (e.g. DS18B20 in parasite power mode) then call
|
||||
// onewire_power() after this is complete to actively drive the line high.
|
||||
//
|
||||
void onewire_write(uint8_t pin, uint8_t v, uint8_t power /* = 0 */) {
|
||||
bool onewire_write(int pin, uint8_t v) {
|
||||
uint8_t bitMask;
|
||||
|
||||
for (bitMask = 0x01; bitMask; bitMask <<= 1) {
|
||||
onewire_write_bit(pin, (bitMask & v)?1:0);
|
||||
if (!_onewire_write_bit(pin, (bitMask & v))) {
|
||||
return false;
|
||||
}
|
||||
if ( !power) {
|
||||
noInterrupts();
|
||||
DIRECT_MODE_INPUT(pin);
|
||||
DIRECT_WRITE_LOW(pin);
|
||||
interrupts();
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
void onewire_write_bytes(uint8_t pin, const uint8_t *buf, uint16_t count, bool power /* = 0 */) {
|
||||
uint16_t i;
|
||||
for (i = 0 ; i < count ; i++)
|
||||
onewire_write(pin, buf[i], ONEWIRE_DEFAULT_POWER);
|
||||
if (!power) {
|
||||
noInterrupts();
|
||||
DIRECT_MODE_INPUT(pin);
|
||||
DIRECT_WRITE_LOW(pin);
|
||||
interrupts();
|
||||
bool onewire_write_bytes(int pin, const uint8_t *buf, size_t count) {
|
||||
size_t i;
|
||||
|
||||
for (i = 0 ; i < count ; i++) {
|
||||
if (!onewire_write(pin, buf[i])) {
|
||||
return false;
|
||||
}
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
// Read a byte
|
||||
//
|
||||
uint8_t onewire_read(uint8_t pin) {
|
||||
int onewire_read(int pin) {
|
||||
uint8_t bitMask;
|
||||
uint8_t r = 0;
|
||||
int r = 0;
|
||||
int bit;
|
||||
|
||||
for (bitMask = 0x01; bitMask; bitMask <<= 1) {
|
||||
if (onewire_read_bit(pin)) r |= bitMask;
|
||||
bit = _onewire_read_bit(pin);
|
||||
if (bit < 0) {
|
||||
return -1;
|
||||
} else if (bit) {
|
||||
r |= bitMask;
|
||||
}
|
||||
}
|
||||
return r;
|
||||
}
|
||||
|
||||
void onewire_read_bytes(uint8_t pin, uint8_t *buf, uint16_t count) {
|
||||
uint16_t i;
|
||||
for (i = 0 ; i < count ; i++)
|
||||
buf[i] = onewire_read(pin);
|
||||
bool onewire_read_bytes(int pin, uint8_t *buf, size_t count) {
|
||||
size_t i;
|
||||
int b;
|
||||
|
||||
for (i = 0 ; i < count ; i++) {
|
||||
b = onewire_read(pin);
|
||||
if (b < 0) return false;
|
||||
buf[i] = b;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
// Do a ROM select
|
||||
//
|
||||
void onewire_select(uint8_t pin, const uint8_t rom[8])
|
||||
{
|
||||
bool onewire_select(int pin, onewire_addr_t addr) {
|
||||
uint8_t i;
|
||||
|
||||
onewire_write(pin, 0x55, ONEWIRE_DEFAULT_POWER); // Choose ROM
|
||||
|
||||
for (i = 0; i < 8; i++) onewire_write(pin, rom[i], ONEWIRE_DEFAULT_POWER);
|
||||
if (!onewire_write(pin, ONEWIRE_SELECT_ROM)) {
|
||||
return false;
|
||||
}
|
||||
|
||||
// Do a ROM skip
|
||||
//
|
||||
void onewire_skip(uint8_t pin)
|
||||
{
|
||||
onewire_write(pin, 0xCC, ONEWIRE_DEFAULT_POWER); // Skip ROM
|
||||
for (i = 0; i < 8; i++) {
|
||||
if (!onewire_write(pin, addr & 0xff)) {
|
||||
return false;
|
||||
}
|
||||
addr >>= 8;
|
||||
}
|
||||
|
||||
void onewire_depower(uint8_t pin)
|
||||
{
|
||||
noInterrupts();
|
||||
DIRECT_MODE_INPUT(pin);
|
||||
interrupts();
|
||||
return true;
|
||||
}
|
||||
|
||||
// You need to use this function to start a search again from the beginning.
|
||||
// You do not need to do it for the first search, though you could.
|
||||
//
|
||||
void onewire_reset_search(uint8_t pin)
|
||||
{
|
||||
bool onewire_skip_rom(int pin) {
|
||||
return onewire_write(pin, ONEWIRE_SKIP_ROM);
|
||||
}
|
||||
|
||||
bool onewire_power(int pin) {
|
||||
// Make sure the bus is not being held low before driving it high, or we
|
||||
// may end up shorting ourselves out.
|
||||
if (!_onewire_wait_for_bus(pin, 10)) return false;
|
||||
|
||||
gpio_enable(pin, GPIO_OUTPUT);
|
||||
gpio_write(pin, 1);
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
void onewire_depower(int pin) {
|
||||
gpio_enable(pin, GPIO_OUT_OPEN_DRAIN);
|
||||
}
|
||||
|
||||
void onewire_search_start(onewire_search_t *search) {
|
||||
// reset the search state
|
||||
LastDiscrepancy[pin] = 0;
|
||||
LastDeviceFlag[pin] = 0;
|
||||
LastFamilyDiscrepancy[pin] = 0;
|
||||
int i;
|
||||
for(i = 7; ; i--) {
|
||||
ROM_NO[pin][i] = 0;
|
||||
if ( i == 0) break;
|
||||
}
|
||||
memset(search, 0, sizeof(*search));
|
||||
}
|
||||
|
||||
// Setup the search to find the device type 'family_code' on the next call
|
||||
// to search(*newAddr) if it is present.
|
||||
//
|
||||
void onewire_target_search(uint8_t pin, uint8_t family_code)
|
||||
{
|
||||
// set the search state to find SearchFamily type devices
|
||||
ROM_NO[pin][0] = family_code;
|
||||
void onewire_search_prefix(onewire_search_t *search, uint8_t family_code) {
|
||||
uint8_t i;
|
||||
for (i = 1; i < 8; i++)
|
||||
ROM_NO[pin][i] = 0;
|
||||
LastDiscrepancy[pin] = 64;
|
||||
LastFamilyDiscrepancy[pin] = 0;
|
||||
LastDeviceFlag[pin] = 0;
|
||||
|
||||
search->rom_no[0] = family_code;
|
||||
for (i = 1; i < 8; i++) {
|
||||
search->rom_no[i] = 0;
|
||||
}
|
||||
search->last_discrepancy = 64;
|
||||
search->last_device_found = false;
|
||||
}
|
||||
|
||||
// Perform a search. If this function returns a '1' then it has
|
||||
// enumerated the next device and you may retrieve the ROM from the
|
||||
// OneWire::address variable. If there are no devices, no further
|
||||
// Perform a search. If the next device has been successfully enumerated, its
|
||||
// ROM address will be returned. If there are no devices, no further
|
||||
// devices, or something horrible happens in the middle of the
|
||||
// enumeration then a 0 is returned. If a new device is found then
|
||||
// its address is copied to newAddr. Use OneWire::reset_search() to
|
||||
// enumeration then ONEWIRE_NONE is returned. Use OneWire::reset_search() to
|
||||
// start over.
|
||||
//
|
||||
// --- Replaced by the one from the Dallas Semiconductor web site ---
|
||||
|
|
@ -210,13 +211,15 @@ void onewire_target_search(uint8_t pin, uint8_t family_code)
|
|||
// Return 1 : device found, ROM number in ROM_NO buffer
|
||||
// 0 : device not found, end of search
|
||||
//
|
||||
uint8_t onewire_search(uint8_t pin, uint8_t *newAddr)
|
||||
{
|
||||
onewire_addr_t onewire_search_next(onewire_search_t *search, int pin) {
|
||||
//TODO: add more checking for read/write errors
|
||||
uint8_t id_bit_number;
|
||||
uint8_t last_zero, rom_byte_number, search_result;
|
||||
uint8_t last_zero, search_result;
|
||||
int rom_byte_number;
|
||||
uint8_t id_bit, cmp_id_bit;
|
||||
|
||||
unsigned char rom_byte_mask, search_direction;
|
||||
onewire_addr_t addr;
|
||||
unsigned char rom_byte_mask;
|
||||
bool search_direction;
|
||||
|
||||
// initialize for search
|
||||
id_bit_number = 1;
|
||||
|
|
@ -226,66 +229,60 @@ uint8_t onewire_search(uint8_t pin, uint8_t *newAddr)
|
|||
search_result = 0;
|
||||
|
||||
// if the last call was not the last one
|
||||
if (!LastDeviceFlag[pin])
|
||||
{
|
||||
if (!search->last_device_found) {
|
||||
// 1-Wire reset
|
||||
if (!onewire_reset(pin))
|
||||
{
|
||||
if (!onewire_reset(pin)) {
|
||||
// reset the search
|
||||
LastDiscrepancy[pin] = 0;
|
||||
LastDeviceFlag[pin] = 0;
|
||||
LastFamilyDiscrepancy[pin] = 0;
|
||||
return 0;
|
||||
search->last_discrepancy = 0;
|
||||
search->last_device_found = false;
|
||||
return ONEWIRE_NONE;
|
||||
}
|
||||
|
||||
// issue the search command
|
||||
onewire_write(pin, 0xF0, ONEWIRE_DEFAULT_POWER);
|
||||
onewire_write(pin, ONEWIRE_SEARCH);
|
||||
|
||||
// loop to do the search
|
||||
do
|
||||
{
|
||||
do {
|
||||
// read a bit and its complement
|
||||
id_bit = onewire_read_bit(pin);
|
||||
cmp_id_bit = onewire_read_bit(pin);
|
||||
id_bit = _onewire_read_bit(pin);
|
||||
cmp_id_bit = _onewire_read_bit(pin);
|
||||
|
||||
// check for no devices on 1-wire
|
||||
if ((id_bit == 1) && (cmp_id_bit == 1))
|
||||
if ((id_bit < 0) || (cmp_id_bit < 0)) {
|
||||
// Read error
|
||||
break;
|
||||
else
|
||||
{
|
||||
} else if ((id_bit == 1) && (cmp_id_bit == 1)) {
|
||||
break;
|
||||
} else {
|
||||
// all devices coupled have 0 or 1
|
||||
if (id_bit != cmp_id_bit)
|
||||
if (id_bit != cmp_id_bit) {
|
||||
search_direction = id_bit; // bit write value for search
|
||||
else
|
||||
{
|
||||
} else {
|
||||
// if this discrepancy if before the Last Discrepancy
|
||||
// on a previous next then pick the same as last time
|
||||
if (id_bit_number < LastDiscrepancy[pin])
|
||||
search_direction = ((ROM_NO[pin][rom_byte_number] & rom_byte_mask) > 0);
|
||||
else
|
||||
if (id_bit_number < search->last_discrepancy) {
|
||||
search_direction = ((search->rom_no[rom_byte_number] & rom_byte_mask) > 0);
|
||||
} else {
|
||||
// if equal to last pick 1, if not then pick 0
|
||||
search_direction = (id_bit_number == LastDiscrepancy[pin]);
|
||||
search_direction = (id_bit_number == search->last_discrepancy);
|
||||
}
|
||||
|
||||
// if 0 was picked then record its position in LastZero
|
||||
if (search_direction == 0)
|
||||
{
|
||||
if (!search_direction) {
|
||||
last_zero = id_bit_number;
|
||||
|
||||
// check for Last discrepancy in family
|
||||
if (last_zero < 9)
|
||||
LastFamilyDiscrepancy[pin] = last_zero;
|
||||
}
|
||||
}
|
||||
|
||||
// set or clear the bit in the ROM byte rom_byte_number
|
||||
// with mask rom_byte_mask
|
||||
if (search_direction == 1)
|
||||
ROM_NO[pin][rom_byte_number] |= rom_byte_mask;
|
||||
else
|
||||
ROM_NO[pin][rom_byte_number] &= ~rom_byte_mask;
|
||||
if (search_direction) {
|
||||
search->rom_no[rom_byte_number] |= rom_byte_mask;
|
||||
} else {
|
||||
search->rom_no[rom_byte_number] &= ~rom_byte_mask;
|
||||
}
|
||||
|
||||
// serial number search direction write bit
|
||||
onewire_write_bit(pin, search_direction);
|
||||
_onewire_write_bit(pin, search_direction);
|
||||
|
||||
// increment the byte counter id_bit_number
|
||||
// and shift the mask rom_byte_mask
|
||||
|
|
@ -293,46 +290,40 @@ uint8_t onewire_search(uint8_t pin, uint8_t *newAddr)
|
|||
rom_byte_mask <<= 1;
|
||||
|
||||
// if the mask is 0 then go to new SerialNum byte rom_byte_number and reset mask
|
||||
if (rom_byte_mask == 0)
|
||||
{
|
||||
if (rom_byte_mask == 0) {
|
||||
rom_byte_number++;
|
||||
rom_byte_mask = 1;
|
||||
}
|
||||
}
|
||||
}
|
||||
while(rom_byte_number < 8); // loop until through all ROM bytes 0-7
|
||||
} while (rom_byte_number < 8); // loop until through all ROM bytes 0-7
|
||||
|
||||
// if the search was successful then
|
||||
if (!(id_bit_number < 65))
|
||||
{
|
||||
// search successful so set LastDiscrepancy,LastDeviceFlag,search_result
|
||||
LastDiscrepancy[pin] = last_zero;
|
||||
if (!(id_bit_number < 65)) {
|
||||
// search successful so set last_discrepancy,last_device_found,search_result
|
||||
search->last_discrepancy = last_zero;
|
||||
|
||||
// check for last device
|
||||
if (LastDiscrepancy[pin] == 0)
|
||||
LastDeviceFlag[pin] = 1;
|
||||
if (search->last_discrepancy == 0) {
|
||||
search->last_device_found = true;
|
||||
}
|
||||
|
||||
search_result = 1;
|
||||
}
|
||||
}
|
||||
|
||||
// if no device found then reset counters so next 'search' will be like a first
|
||||
if (!search_result || !ROM_NO[pin][0])
|
||||
{
|
||||
LastDiscrepancy[pin] = 0;
|
||||
LastDeviceFlag[pin] = 0;
|
||||
LastFamilyDiscrepancy[pin] = 0;
|
||||
search_result = 0;
|
||||
if (!search_result || !search->rom_no[0]) {
|
||||
search->last_discrepancy = 0;
|
||||
search->last_device_found = false;
|
||||
return ONEWIRE_NONE;
|
||||
} else {
|
||||
addr = 0;
|
||||
for (rom_byte_number = 7; rom_byte_number >= 0; rom_byte_number--) {
|
||||
addr = (addr << 8) | search->rom_no[rom_byte_number];
|
||||
}
|
||||
else
|
||||
{
|
||||
for (rom_byte_number = 0; rom_byte_number < 8; rom_byte_number++)
|
||||
{
|
||||
newAddr[rom_byte_number] = ROM_NO[pin][rom_byte_number];
|
||||
//printf("Ok I found something at %d - %x...\n",rom_byte_number, newAddr[rom_byte_number]);
|
||||
//printf("Ok I found something at %08x%08x...\n", (uint32_t)(addr >> 32), (uint32_t)addr);
|
||||
}
|
||||
}
|
||||
return search_result;
|
||||
return addr;
|
||||
}
|
||||
|
||||
// The 1-Wire CRC scheme is described in Maxim Application Note 27:
|
||||
|
|
@ -371,12 +362,11 @@ static const uint8_t dscrc_table[] = {
|
|||
// compared to all those delayMicrosecond() calls. But I got
|
||||
// confused, so I use this table from the examples.)
|
||||
//
|
||||
uint8_t onewire_crc8(const uint8_t *addr, uint8_t len)
|
||||
{
|
||||
uint8_t onewire_crc8(const uint8_t *data, uint8_t len) {
|
||||
uint8_t crc = 0;
|
||||
|
||||
while (len--) {
|
||||
crc = pgm_read_byte(dscrc_table + (crc ^ *addr++));
|
||||
crc = pgm_read_byte(dscrc_table + (crc ^ *data++));
|
||||
}
|
||||
return crc;
|
||||
}
|
||||
|
|
@ -385,14 +375,12 @@ uint8_t onewire_crc8(const uint8_t *addr, uint8_t len)
|
|||
// Compute a Dallas Semiconductor 8 bit CRC directly.
|
||||
// this is much slower, but much smaller, than the lookup table.
|
||||
//
|
||||
uint8_t onewire_crc8(const uint8_t *addr, uint8_t len)
|
||||
{
|
||||
uint8_t onewire_crc8(const uint8_t *data, uint8_t len) {
|
||||
uint8_t crc = 0;
|
||||
|
||||
while (len--) {
|
||||
uint8_t inbyte = *addr++;
|
||||
uint8_t i;
|
||||
for (i = 8; i; i--) {
|
||||
uint8_t inbyte = *data++;
|
||||
for (int i = 8; i; i--) {
|
||||
uint8_t mix = (crc ^ inbyte) & 0x01;
|
||||
crc >>= 1;
|
||||
if (mix) crc ^= 0x8C;
|
||||
|
|
@ -423,9 +411,8 @@ uint8_t onewire_crc8(const uint8_t *addr, uint8_t len)
|
|||
// *not* at a 16-bit integer.
|
||||
// @param crc - The crc starting value (optional)
|
||||
// @return 1, iff the CRC matches.
|
||||
bool onewire_check_crc16(const uint8_t* input, uint16_t len, const uint8_t* inverted_crc, uint16_t crc)
|
||||
{
|
||||
crc = ~onewire_crc16(input, len, crc);
|
||||
bool onewire_check_crc16(const uint8_t* input, size_t len, const uint8_t* inverted_crc, uint16_t crc_iv) {
|
||||
uint16_t crc = ~onewire_crc16(input, len, crc_iv);
|
||||
return (crc & 0xFF) == inverted_crc[0] && (crc >> 8) == inverted_crc[1];
|
||||
}
|
||||
|
||||
|
|
@ -441,8 +428,8 @@ bool onewire_check_crc16(const uint8_t* input, uint16_t len, const uint8_t* inve
|
|||
// @param len - How many bytes to use.
|
||||
// @param crc - The crc starting value (optional)
|
||||
// @return The CRC16, as defined by Dallas Semiconductor.
|
||||
uint16_t onewire_crc16(const uint8_t* input, uint16_t len, uint16_t crc)
|
||||
{
|
||||
uint16_t onewire_crc16(const uint8_t* input, size_t len, uint16_t crc_iv) {
|
||||
uint16_t crc = crc_iv;
|
||||
static const uint8_t oddparity[16] =
|
||||
{ 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 };
|
||||
|
||||
|
|
|
|||
|
|
@ -4,135 +4,232 @@
|
|||
#include <espressif/esp_misc.h> // sdk_os_delay_us
|
||||
#include "FreeRTOS.h"
|
||||
|
||||
// 1 for keeping the parasitic power on H
|
||||
#define ONEWIRE_DEFAULT_POWER 1
|
||||
/** @file onewire.h
|
||||
*
|
||||
* Routines to access devices using the Dallas Semiconductor 1-Wire(tm)
|
||||
* protocol.
|
||||
*/
|
||||
|
||||
// Maximum number of devices.
|
||||
#define ONEWIRE_NUM 20
|
||||
|
||||
// You can exclude certain features from OneWire. In theory, this
|
||||
// might save some space. In practice, the compiler automatically
|
||||
// removes unused code (technically, the linker, using -fdata-sections
|
||||
// and -ffunction-sections when compiling, and Wl,--gc-sections
|
||||
// when linking), so most of these will not result in any code size
|
||||
// reduction. Well, unless you try to use the missing features
|
||||
// and redesign your program to not need them! ONEWIRE_CRC8_TABLE
|
||||
// is the exception, because it selects a fast but large algorithm
|
||||
// or a small but slow algorithm.
|
||||
|
||||
// Select the table-lookup method of computing the 8-bit CRC
|
||||
// by setting this to 1. The lookup table enlarges code size by
|
||||
// about 250 bytes. It does NOT consume RAM (but did in very
|
||||
// old versions of OneWire). If you disable this, a slower
|
||||
// but very compact algorithm is used.
|
||||
/** Select the table-lookup method of computing the 8-bit CRC
|
||||
* by setting this to 1 during compilation. The lookup table enlarges code
|
||||
* size by about 250 bytes. By default, a slower but very compact algorithm
|
||||
* is used.
|
||||
*/
|
||||
#ifndef ONEWIRE_CRC8_TABLE
|
||||
#define ONEWIRE_CRC8_TABLE 0
|
||||
#endif
|
||||
|
||||
// Platform specific I/O definitions
|
||||
#define noInterrupts portDISABLE_INTERRUPTS
|
||||
#define interrupts portENABLE_INTERRUPTS
|
||||
#define delayMicroseconds sdk_os_delay_us
|
||||
/** Type used to hold all 1-Wire device ROM addresses (64-bit) */
|
||||
typedef uint64_t onewire_addr_t;
|
||||
|
||||
#define DIRECT_READ(pin) gpio_read(pin)
|
||||
#define DIRECT_MODE_INPUT(pin) gpio_enable(pin, GPIO_INPUT)
|
||||
#define DIRECT_MODE_OUTPUT(pin) gpio_enable(pin, GPIO_OUTPUT)
|
||||
#define DIRECT_WRITE_LOW(pin) gpio_write(pin, 0)
|
||||
#define DIRECT_WRITE_HIGH(pin) gpio_write(pin, 1)
|
||||
/** Structure to contain the current state for onewire_search_next(), etc */
|
||||
typedef struct {
|
||||
uint8_t rom_no[8];
|
||||
uint8_t last_discrepancy;
|
||||
bool last_device_found;
|
||||
} onewire_search_t;
|
||||
|
||||
void onewire_init(uint8_t pin);
|
||||
/** ::ONEWIRE_NONE is an invalid ROM address that will never occur in a device
|
||||
* (CRC mismatch), and so can be useful as an indicator for "no-such-device",
|
||||
* etc.
|
||||
*/
|
||||
#define ONEWIRE_NONE ((onewire_addr_t)(0xffffffffffffffffLL))
|
||||
|
||||
// Perform a 1-Wire reset cycle. Returns 1 if a device responds
|
||||
// with a presence pulse. Returns 0 if there is no device or the
|
||||
// bus is shorted or otherwise held low for more than 250uS
|
||||
uint8_t onewire_reset(uint8_t pin);
|
||||
/** Perform a 1-Wire reset cycle.
|
||||
*
|
||||
* @param pin The GPIO pin connected to the 1-Wire bus.
|
||||
*
|
||||
* @returns `true` if at least one device responds with a presence pulse,
|
||||
* `false` if no devices were detected (or the bus is shorted, etc)
|
||||
*/
|
||||
bool onewire_reset(int pin);
|
||||
|
||||
// Issue a 1-Wire rom select command, you do the reset first.
|
||||
void onewire_select(uint8_t pin, const uint8_t rom[8]);
|
||||
/** Issue a 1-Wire rom select command to select a particular device.
|
||||
*
|
||||
* It is necessary to call onewire_reset() before calling this function.
|
||||
*
|
||||
* @param pin The GPIO pin connected to the 1-Wire bus.
|
||||
* @param addr The ROM address of the device to select
|
||||
*
|
||||
* @returns `true` if the "ROM select" command could be succesfully issued,
|
||||
* `false` if there was an error.
|
||||
*/
|
||||
bool onewire_select(int pin, const onewire_addr_t addr);
|
||||
|
||||
// Issue a 1-Wire rom skip command, to address all on bus.
|
||||
void onewire_skip(uint8_t pin);
|
||||
/** Issue a 1-Wire "skip ROM" command to select *all* devices on the bus.
|
||||
*
|
||||
* It is necessary to call onewire_reset() before calling this function.
|
||||
*
|
||||
* @param pin The GPIO pin connected to the 1-Wire bus.
|
||||
*
|
||||
* @returns `true` if the "skip ROM" command could be succesfully issued,
|
||||
* `false` if there was an error.
|
||||
*/
|
||||
bool onewire_skip_rom(int pin);
|
||||
|
||||
// Write a byte. If 'power' is one then the wire is held high at
|
||||
// the end for parasitically powered devices. You are responsible
|
||||
// for eventually depowering it by calling depower() or doing
|
||||
// another read or write.
|
||||
void onewire_write(uint8_t pin, uint8_t v, uint8_t power);
|
||||
/** Write a byte on the onewire bus.
|
||||
*
|
||||
* The writing code uses open-drain mode and expects the pullup resistor to
|
||||
* pull the line high when not driven low. If you need strong power after the
|
||||
* write (e.g. DS18B20 in parasite power mode) then call onewire_power() after
|
||||
* this is complete to actively drive the line high.
|
||||
*
|
||||
* @param pin The GPIO pin connected to the 1-Wire bus.
|
||||
* @param v The byte value to write
|
||||
*
|
||||
* @returns `true` if successful, `false` on error.
|
||||
*/
|
||||
bool onewire_write(int pin, uint8_t v);
|
||||
|
||||
void onewire_write_bytes(uint8_t pin, const uint8_t *buf, uint16_t count, bool power);
|
||||
/** Write multiple bytes on the 1-Wire bus.
|
||||
*
|
||||
* See onewire_write() for more info.
|
||||
*
|
||||
* @param pin The GPIO pin connected to the 1-Wire bus.
|
||||
* @param buf A pointer to the buffer of bytes to be written
|
||||
* @param count Number of bytes to write
|
||||
*
|
||||
* @returns `true` if all bytes written successfully, `false` on error.
|
||||
*/
|
||||
bool onewire_write_bytes(int pin, const uint8_t *buf, size_t count);
|
||||
|
||||
// Read a byte.
|
||||
uint8_t onewire_read(uint8_t pin);
|
||||
/** Read a byte from a 1-Wire device.
|
||||
*
|
||||
* @param pin The GPIO pin connected to the 1-Wire bus.
|
||||
*
|
||||
* @returns the read byte on success, negative value on error.
|
||||
*/
|
||||
int onewire_read(int pin);
|
||||
|
||||
void onewire_read_bytes(uint8_t pin, uint8_t *buf, uint16_t count);
|
||||
/** Read multiple bytes from a 1-Wire device.
|
||||
*
|
||||
* @param pin The GPIO pin connected to the 1-Wire bus.
|
||||
* @param buf A pointer to the buffer to contain the read bytes
|
||||
* @param count Number of bytes to read
|
||||
*
|
||||
* @returns `true` on success, `false` on error.
|
||||
*/
|
||||
bool onewire_read_bytes(int pin, uint8_t *buf, size_t count);
|
||||
|
||||
// Write a bit. The bus is always left powered at the end, see
|
||||
// note in write() about that.
|
||||
// void onewire_write_bit(uint8_t pin, uint8_t v);
|
||||
/** Actively drive the bus high to provide extra power for certain operations
|
||||
* of parasitically-powered devices.
|
||||
*
|
||||
* For parasitically-powered devices which need more power than can be
|
||||
* provided via the normal pull-up resistor, it may be necessary for some
|
||||
* operations to drive the bus actively high. This function can be used to
|
||||
* perform that operation.
|
||||
*
|
||||
* The bus can be depowered once it is no longer needed by calling
|
||||
* onewire_depower(), or it will be depowered automatically the next time
|
||||
* onewire_reset() is called to start another command.
|
||||
*
|
||||
* Note: Make sure the device(s) you are powering will not pull more current
|
||||
* than the ESP8266 is able to supply via its GPIO pins (this is especially
|
||||
* important when multiple devices are on the same bus and they are all
|
||||
* performing a power-intensive operation at the same time (i.e. multiple
|
||||
* DS18B20 sensors, which have all been given a "convert T" operation by using
|
||||
* onewire_skip_rom())).
|
||||
*
|
||||
* Note: This routine will check to make sure that the bus is already high
|
||||
* before driving it, to make sure it doesn't attempt to drive it high while
|
||||
* something else is pulling it low (which could cause a reset or damage the
|
||||
* ESP8266).
|
||||
*
|
||||
* @param pin The GPIO pin connected to the 1-Wire bus.
|
||||
*
|
||||
* @returns `true` on success, `false` on error.
|
||||
*/
|
||||
bool onewire_power(int pin);
|
||||
|
||||
// Read a bit.
|
||||
// uint8_t onewire_read_bit(uint8_t pin);
|
||||
/** Stop forcing power onto the bus.
|
||||
*
|
||||
* You only need to do this if you previously called onewire_power() to drive
|
||||
* the bus high and now want to allow it to float instead. Note that
|
||||
* onewire_reset() will also automatically depower the bus first, so you do
|
||||
* not need to call this first if you just want to start a new operation.
|
||||
*
|
||||
* @param pin The GPIO pin connected to the 1-Wire bus.
|
||||
*/
|
||||
void onewire_depower(int pin);
|
||||
|
||||
// Stop forcing power onto the bus. You only need to do this if
|
||||
// you used the 'power' flag to write() or used a write_bit() call
|
||||
// and aren't about to do another read or write. You would rather
|
||||
// not leave this powered if you don't have to, just in case
|
||||
// someone shorts your bus.
|
||||
void onewire_depower(uint8_t pin);
|
||||
/** Clear the search state so that it will start from the beginning on the next
|
||||
* call to onewire_search_next().
|
||||
*
|
||||
* @param search The onewire_search_t structure to reset.
|
||||
*/
|
||||
void onewire_search_start(onewire_search_t *search);
|
||||
|
||||
// Clear the search state so that if will start from the beginning again.
|
||||
void onewire_reset_search(uint8_t pin);
|
||||
/** Setup the search to search for devices with the specified "family code".
|
||||
*
|
||||
* @param search The onewire_search_t structure to update.
|
||||
* @param family_code The "family code" to search for.
|
||||
*/
|
||||
void onewire_search_prefix(onewire_search_t *search, uint8_t family_code);
|
||||
|
||||
// Setup the search to find the device type 'family_code' on the next call
|
||||
// to search(*newAddr) if it is present.
|
||||
void onewire_target_search(uint8_t pin, uint8_t family_code);
|
||||
/** Search for the next device on the bus.
|
||||
*
|
||||
* The order of returned device addresses is deterministic. You will always
|
||||
* get the same devices in the same order.
|
||||
*
|
||||
* @returns the address of the next device on the bus, or ::ONEWIRE_NONE if
|
||||
* there is no next address. ::ONEWIRE_NONE might also mean that the bus is
|
||||
* shorted, there are no devices, or you have already retrieved all of them.
|
||||
*
|
||||
* It might be a good idea to check the CRC to make sure you didn't get
|
||||
* garbage.
|
||||
*/
|
||||
onewire_addr_t onewire_search_next(onewire_search_t *search, int pin);
|
||||
|
||||
// Look for the next device. Returns 1 if a new address has been
|
||||
// returned. A zero might mean that the bus is shorted, there are
|
||||
// no devices, or you have already retrieved all of them. It
|
||||
// might be a good idea to check the CRC to make sure you didn't
|
||||
// get garbage. The order is deterministic. You will always get
|
||||
// the same devices in the same order.
|
||||
uint8_t onewire_search(uint8_t pin, uint8_t *newAddr);
|
||||
/** Compute a Dallas Semiconductor 8 bit CRC.
|
||||
*
|
||||
* These are used in the ROM address and scratchpad registers to verify the
|
||||
* transmitted data is correct.
|
||||
*/
|
||||
uint8_t onewire_crc8(const uint8_t *data, uint8_t len);
|
||||
|
||||
// Compute a Dallas Semiconductor 8 bit CRC, these are used in the
|
||||
// ROM and scratchpad registers.
|
||||
uint8_t onewire_crc8(const uint8_t *addr, uint8_t len);
|
||||
/** Compute the 1-Wire CRC16 and compare it against the received CRC.
|
||||
*
|
||||
* Example usage (reading a DS2408):
|
||||
* @code
|
||||
* // Put everything in a buffer so we can compute the CRC easily.
|
||||
* uint8_t buf[13];
|
||||
* buf[0] = 0xF0; // Read PIO Registers
|
||||
* buf[1] = 0x88; // LSB address
|
||||
* buf[2] = 0x00; // MSB address
|
||||
* onewire_write_bytes(pin, buf, 3); // Write 3 cmd bytes
|
||||
* onewire_read_bytes(pin, buf+3, 10); // Read 6 data bytes, 2 0xFF, 2 CRC16
|
||||
* if (!onewire_check_crc16(buf, 11, &buf[11])) {
|
||||
* // TODO: Handle error.
|
||||
* }
|
||||
* @endcode
|
||||
*
|
||||
* @param input Array of bytes to checksum.
|
||||
* @param len Number of bytes in `input`
|
||||
* @param inverted_crc The two CRC16 bytes in the received data.
|
||||
* This should just point into the received data,
|
||||
* *not* at a 16-bit integer.
|
||||
* @param crc_iv The crc starting value (optional)
|
||||
*
|
||||
* @returns `true` if the CRC matches, `false` otherwise.
|
||||
*/
|
||||
bool onewire_check_crc16(const uint8_t* input, size_t len, const uint8_t* inverted_crc, uint16_t crc_iv);
|
||||
|
||||
// Compute the 1-Wire CRC16 and compare it against the received CRC.
|
||||
// Example usage (reading a DS2408):
|
||||
// // Put everything in a buffer so we can compute the CRC easily.
|
||||
// uint8_t buf[13];
|
||||
// buf[0] = 0xF0; // Read PIO Registers
|
||||
// buf[1] = 0x88; // LSB address
|
||||
// buf[2] = 0x00; // MSB address
|
||||
// WriteBytes(net, buf, 3); // Write 3 cmd bytes
|
||||
// ReadBytes(net, buf+3, 10); // Read 6 data bytes, 2 0xFF, 2 CRC16
|
||||
// if (!CheckCRC16(buf, 11, &buf[11])) {
|
||||
// // Handle error.
|
||||
// }
|
||||
//
|
||||
// @param input - Array of bytes to checksum.
|
||||
// @param len - How many bytes to use.
|
||||
// @param inverted_crc - The two CRC16 bytes in the received data.
|
||||
// This should just point into the received data,
|
||||
// *not* at a 16-bit integer.
|
||||
// @param crc - The crc starting value (optional)
|
||||
// @return True, iff the CRC matches.
|
||||
bool onewire_check_crc16(const uint8_t* input, uint16_t len, const uint8_t* inverted_crc, uint16_t crc);
|
||||
|
||||
// Compute a Dallas Semiconductor 16 bit CRC. This is required to check
|
||||
// the integrity of data received from many 1-Wire devices. Note that the
|
||||
// CRC computed here is *not* what you'll get from the 1-Wire network,
|
||||
// for two reasons:
|
||||
// 1) The CRC is transmitted bitwise inverted.
|
||||
// 2) Depending on the endian-ness of your processor, the binary
|
||||
// representation of the two-byte return value may have a different
|
||||
// byte order than the two bytes you get from 1-Wire.
|
||||
// @param input - Array of bytes to checksum.
|
||||
// @param len - How many bytes to use.
|
||||
// @param crc - The crc starting value (optional)
|
||||
// @return The CRC16, as defined by Dallas Semiconductor.
|
||||
uint16_t onewire_crc16(const uint8_t* input, uint16_t len, uint16_t crc);
|
||||
/** Compute a Dallas Semiconductor 16 bit CRC.
|
||||
*
|
||||
* This is required to check the integrity of data received from many 1-Wire
|
||||
* devices. Note that the CRC computed here is *not* what you'll get from the
|
||||
* 1-Wire network, for two reasons:
|
||||
* 1. The CRC is transmitted bitwise inverted.
|
||||
* 2. Depending on the endian-ness of your processor, the binary
|
||||
* representation of the two-byte return value may have a different
|
||||
* byte order than the two bytes you get from 1-Wire.
|
||||
*
|
||||
* @param input Array of bytes to checksum.
|
||||
* @param len How many bytes are in `input`.
|
||||
* @param crc_iv The crc starting value (optional)
|
||||
*
|
||||
* @returns the CRC16, as defined by Dallas Semiconductor.
|
||||
*/
|
||||
uint16_t onewire_crc16(const uint8_t* input, size_t len, uint16_t crc_iv);
|
||||
|
||||
#endif
|
||||
|
|
|
|||
Loading…
Reference in a new issue