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Fix delay in DS18B20 driver

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There is a bug in the driver for DS18B20: instead of delaying for 750ms it waits only for 750us, which obviously causes that read temprature is not valid (it's default 85 degrees).
This commit is contained in:
darksv 2016-02-28 11:30:16 +01:00
parent a32d1099fa
commit dc2c4be4e9
1 changed files with 7 additions and 2 deletions
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9
extras/ds18b20/ds18b20.c
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@ -1,3 +1,6 @@
#include "FreeRTOS.h"
#include "task.h"
#include "onewire/onewire.h" #include "onewire/onewire.h"
#include "ds18b20.h" #include "ds18b20.h"
@ -29,7 +32,9 @@ uint8_t ds18b20_read_all(uint8_t pin, ds_sensor_t *result) {
onewire_reset(pin); onewire_reset(pin);
onewire_select(pin, addr); onewire_select(pin, addr);
onewire_write(pin, DS1820_CONVERT_T, ONEWIRE_DEFAULT_POWER); onewire_write(pin, DS1820_CONVERT_T, ONEWIRE_DEFAULT_POWER);
sdk_os_delay_us(750);
vTaskDelay(750 / portTICK_RATE_MS);
onewire_reset(pin); onewire_reset(pin);
onewire_select(pin, addr); onewire_select(pin, addr);
onewire_write(pin, DS1820_READ_SCRATCHPAD, ONEWIRE_DEFAULT_POWER); onewire_write(pin, DS1820_READ_SCRATCHPAD, ONEWIRE_DEFAULT_POWER);
@ -70,7 +75,7 @@ float ds18b20_read_single(uint8_t pin) {
onewire_write(pin, DS1820_SKIP_ROM, ONEWIRE_DEFAULT_POWER); onewire_write(pin, DS1820_SKIP_ROM, ONEWIRE_DEFAULT_POWER);
onewire_write(pin, DS1820_CONVERT_T, ONEWIRE_DEFAULT_POWER); onewire_write(pin, DS1820_CONVERT_T, ONEWIRE_DEFAULT_POWER);
sdk_os_delay_us(750); vTaskDelay(750 / portTICK_RATE_MS);
onewire_reset(pin); onewire_reset(pin);
onewire_write(pin, DS1820_SKIP_ROM, ONEWIRE_DEFAULT_POWER); onewire_write(pin, DS1820_SKIP_ROM, ONEWIRE_DEFAULT_POWER);