Driver for PCA9685 + example

2016-12-19 05:53:07 +05:00 · 2016-12-19 05:53:07 +05:00 · e96fb4242e
commit e96fb4242e
parent 7432c019f7
5 changed files with 409 additions and 0 deletions
--- a/extras/pca9685/pca9685.c
+++ b/extras/pca9685/pca9685.c
@ -0,0 +1,217 @@
+/**
+ * Driver for 16-channel, 12-bit PWM PCA9685
+ *
+ * Part of esp-open-rtos
+ * Copyright (C) 2016 Ruslan V. Uss <unclerus@gmail.com>
+ * BSD Licensed as described in the file LICENSE
+ */
+#include "pca9685.h"
+
+#include <i2c/i2c.h>
+#include <espressif/esp_common.h>
+
+#define REG_MODE1      0x00
+#define REG_MODE2      0x01
+#define REG_SUBADR1    0x02
+#define REG_SUBADR2    0x03
+#define REG_SUBADR3    0x04
+#define REG_ALLCALLADR 0x05
+#define REG_LEDX       0x06
+#define REG_ALL_LED    0xfa
+#define REG_PRE_SCALE  0xfe
+
+#define MODE1_RESTART (1 << 7)
+#define MODE1_EXTCLK  (1 << 6)
+#define MODE1_AI      (1 << 5)
+#define MODE1_SLEEP   (1 << 4)
+
+#define MODE1_SUB_BIT 3
+
+#define MODE2_INVRT   (1 << 4)
+#define MODE2_OUTDRV  (1 << 2)
+
+#define LED_FULL_ON_OFF (1 << 4)
+
+#define REG_LED_N(x)  (REG_LEDX + (x) * 4)
+#define OFFS_REG_LED_ON  1
+#define OFFS_REG_LED_OFF 3
+
+#define INTERNAL_FREQ 25000000
+
+#define MIN_PRESCALER 0x03
+#define MAX_PRESCALER 0xff
+#define MAX_CHANNEL   15
+#define MAX_SUBADDR   2
+
+#define WAKEUP_DELAY_US 500
+
+//#define PCA9685_DEBUG
+
+#ifdef PCA9685_DEBUG
+#include <stdio.h>
+#define debug(fmt, ...) printf("%s: " fmt "\n", "PCA9685", ## __VA_ARGS__)
+#else
+#define debug(fmt, ...)
+#endif
+
+inline static uint32_t round_div(uint32_t x, uint32_t y)
+{
+    return (x + y / 2) / y;
+}
+
+inline static void write_reg(uint8_t addr, uint8_t reg, uint8_t val)
+{
+    uint8_t data[2] = { reg, val };
+    if (!i2c_slave_write(addr, data, 2))
+        debug("Could not write 0x%02x to 0x%02x, addr = 0x%02x", reg, val, addr);
+}
+
+inline static uint8_t read_reg(uint8_t addr, uint8_t reg)
+{
+    uint8_t res = 0;
+    if (!i2c_slave_read(addr, reg, &res, 1))
+        debug("Could not read from 0x%02x, addr = 0x%02x", reg, addr);
+    return res;
+}
+
+inline static void update_reg(uint8_t addr, uint8_t reg, uint8_t mask, uint8_t val)
+{
+    write_reg(addr, reg, (read_reg(addr, reg) & ~mask) | val);
+}
+
+void pca9685_init(uint8_t addr)
+{
+    // Enable autoincrement
+    update_reg(addr, REG_MODE1, MODE1_AI, MODE1_AI);
+}
+
+bool pca9685_set_subaddr(uint8_t addr, uint8_t num, uint8_t subaddr, bool enable)
+{
+    if (num > MAX_SUBADDR)
+    {
+        debug("Invalid subaddress number: %d", num);
+        return false;
+    }
+
+    write_reg(addr, REG_SUBADR1 + num, subaddr << 1);
+
+    uint8_t mask = 1 << (MODE1_SUB_BIT - num);
+    update_reg(addr, REG_MODE1, mask, enable ? mask : 0);
+
+    return true;
+}
+
+bool pca9685_is_sleeping(uint8_t addr)
+{
+    return (read_reg(addr, REG_MODE1) & MODE1_SLEEP) != 0;
+}
+
+void pca9685_sleep(uint8_t addr, bool sleep)
+{
+    update_reg(addr, REG_MODE1, MODE1_SLEEP, sleep ? MODE1_SLEEP : 0);
+    if (!sleep)
+        sdk_os_delay_us(WAKEUP_DELAY_US);
+}
+
+void pca9685_restart(uint8_t addr)
+{
+    uint8_t mode = read_reg(addr, REG_MODE1);
+    if (mode & MODE1_RESTART)
+    {
+        write_reg(addr, REG_MODE1, mode & ~MODE1_SLEEP);
+        sdk_os_delay_us(WAKEUP_DELAY_US);
+    }
+    write_reg(addr, REG_MODE1, (mode & ~MODE1_SLEEP) | MODE1_RESTART);
+}
+
+bool pca9685_is_output_inverted(uint8_t addr)
+{
+    return (read_reg(addr, REG_MODE2) & MODE2_INVRT) != 0;
+}
+
+void pca9685_set_output_inverted(uint8_t addr, bool inverted)
+{
+    update_reg(addr, REG_MODE2, MODE2_INVRT, inverted ? MODE2_INVRT : 0);
+}
+
+bool pca9685_get_output_open_drain(uint8_t addr)
+{
+    return (read_reg(addr, REG_MODE2) & MODE2_OUTDRV) == 0;
+}
+
+void pca9685_set_output_open_drain(uint8_t addr, bool open_drain)
+{
+    update_reg(addr, REG_MODE2, MODE2_OUTDRV, open_drain ? 0 : MODE2_OUTDRV);
+}
+
+uint8_t pca9685_get_prescaler(uint8_t addr)
+{
+    return read_reg(addr, REG_PRE_SCALE);
+}
+
+bool pca9685_set_prescaler(uint8_t addr, uint8_t prescaler)
+{
+    if (prescaler < MIN_PRESCALER)
+    {
+        debug("Inavlid prescaler value: %d", prescaler);
+        return false;
+    }
+
+    pca9685_sleep(addr, true);
+    write_reg(addr, REG_PRE_SCALE, prescaler);
+    pca9685_sleep(addr, false);
+    return true;
+}
+
+uint16_t pca9685_get_pwm_frequency(uint8_t addr)
+{
+    return INTERNAL_FREQ / ((uint32_t)4096 * (read_reg(addr, REG_PRE_SCALE) + 1));
+}
+
+bool pca9685_set_pwm_frequency(uint8_t addr, uint16_t freq)
+{
+    uint16_t prescaler = round_div(INTERNAL_FREQ, (uint32_t)4096 * freq) - 1;
+    if (prescaler < MIN_PRESCALER || prescaler > MAX_PRESCALER)
+    {
+        debug("Inavlid prescaler value: %d", prescaler);
+        return false;
+    }
+
+    return pca9685_set_prescaler(addr, prescaler);
+}
+
+void pca9685_set_pwm_value(uint8_t addr, uint8_t channel, uint16_t val)
+{
+    uint8_t reg = channel > MAX_CHANNEL ? REG_ALL_LED : REG_LED_N(channel);
+
+    if (val == 0)
+    {
+        // Full off
+        write_reg(addr, reg + OFFS_REG_LED_OFF, LED_FULL_ON_OFF);
+    }
+    else if (val < 4096)
+    {
+        // Normal
+        uint8_t buf[5] = { reg, 0, 0, val, val >> 8 };
+        i2c_slave_write(addr, buf, 5);
+    }
+    else
+    {
+        // Full on
+        write_reg(addr, reg + OFFS_REG_LED_ON, LED_FULL_ON_OFF);
+    }
+}
+
+bool pca9685_set_pwm_values(uint8_t addr, uint8_t first_ch, uint8_t channels, const uint16_t *values)
+{
+    if (channels == 0 || first_ch + channels - 1 > MAX_CHANNEL)
+    {
+        debug("Invalid channels");
+        return false;
+    }
+
+    for (uint8_t i = 0; i < channels; i ++)
+        pca9685_set_pwm_value(addr, first_ch + i, values [i]);
+
+    return true;
+}