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style: enforce coding standard — headers, @brief on #define, Doxygen on statics, remove _ prefix, max 8 lines per function

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This commit is contained in:
Kevin Thomas
2026-04-16 22:44:43 -04:00
parent 0833c32c94
commit 433263eac0
309 changed files with 10464 additions and 6668 deletions
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0x001d_static-conditionals/servo.c
+39 -21
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@@ -32,46 +32,66 @@
#include "hardware/pwm.h"
#include "hardware/clocks.h"
// Default servo pulse range (SG90 typical)
/** @brief Default minimum pulse width in microseconds */
static const uint16_t SERVO_DEFAULT_MIN_US = 1000;
/** @brief Default maximum pulse width in microseconds */
static const uint16_t SERVO_DEFAULT_MAX_US = 2000;
// internal state
/** @brief GPIO pin assigned to the servo */
static uint8_t servo_pin = 0;
/** @brief PWM hardware slice for the servo pin */
static uint servo_slice = 0;
/** @brief PWM channel within the servo slice */
static uint servo_chan = 0;
static uint32_t servo_wrap = 20000 - 1; // wrap to map microseconds for 50Hz
/** @brief PWM counter wrap value for 50 Hz servo */
static uint32_t servo_wrap = 20000 - 1;
/** @brief Servo PWM frequency in Hz */
static float servo_hz = 50.0f;
/** @brief Flag indicating servo has been initialized */
static bool servo_initialized = false;
// Convert microsecond pulse to PWM level based on wrap and frequency
/**
* @brief Convert a pulse width in microseconds to a PWM counter level
*
* Uses the configured PWM wrap and servo frequency to map pulse time
* into the channel compare value expected by the PWM hardware.
*
* @param pulse_us Pulse width in microseconds
* @return uint32_t PWM level suitable for pwm_set_chan_level()
*/
static uint32_t pulse_us_to_level(uint32_t pulse_us) {
const float period_us = 1000000.0f / servo_hz; // 20000us
const float period_us = 1000000.0f / servo_hz;
float counts_per_us = (servo_wrap + 1) / period_us;
return (uint32_t)(pulse_us * counts_per_us + 0.5f);
}
void servo_init(uint8_t pin) {
servo_pin = pin;
// Configure GPIO for PWM
gpio_set_function(servo_pin, GPIO_FUNC_PWM);
servo_slice = pwm_gpio_to_slice_num(servo_pin);
servo_chan = pwm_gpio_to_channel(servo_pin);
/**
* @brief Build and apply the PWM slice configuration for 50 Hz servo
*
* Computes the clock divider from the system clock to achieve the
* target servo frequency with the chosen wrap value, then starts
* the PWM slice.
*/
static void apply_servo_config(void) {
pwm_config config = pwm_get_default_config();
// Calculate clock divider to achieve 50 Hz with our chosen wrap
const uint32_t sys_clock_hz = clock_get_hz(clk_sys);
float clock_div = (float)sys_clock_hz / (servo_hz * (servo_wrap + 1));
pwm_config_set_clkdiv(&config, clock_div);
pwm_config_set_wrap(&config, servo_wrap);
pwm_init(servo_slice, &config, true);
}
void servo_init(uint8_t pin) {
servo_pin = pin;
gpio_set_function(servo_pin, GPIO_FUNC_PWM);
servo_slice = pwm_gpio_to_slice_num(servo_pin);
servo_chan = pwm_gpio_to_channel(servo_pin);
apply_servo_config();
servo_initialized = true;
}
void servo_set_pulse_us(uint16_t pulse_us) {
if (servo_pin == 0) return; // not initialized
// clamp to defaults
if (!servo_initialized) return;
if (pulse_us < SERVO_DEFAULT_MIN_US) pulse_us = SERVO_DEFAULT_MIN_US;
if (pulse_us > SERVO_DEFAULT_MAX_US) pulse_us = SERVO_DEFAULT_MAX_US;
uint32_t level = pulse_us_to_level(pulse_us);
@@ -81,9 +101,7 @@ void servo_set_pulse_us(uint16_t pulse_us) {
void servo_set_angle(float degrees) {
if (degrees < 0.0f) degrees = 0.0f;
if (degrees > 180.0f) degrees = 180.0f;
// linear map 0..180 -> min_us..max_us
float ratio = degrees / 180.0f;
uint16_t pulse = (uint16_t)(SERVO_DEFAULT_MIN_US + ratio * (SERVO_DEFAULT_MAX_US - SERVO_DEFAULT_MIN_US) + 0.5f);
servo_set_pulse_us(pulse);
}
#
}