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pwm generation and tip driving

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This commit is contained in:
Alessandro Mauri 2026-04-26 22:11:19 +02:00
parent adcf08f236
commit 4ffb554d43
1 changed files with 107 additions and 13 deletions
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120
fw/main.c
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@ -31,6 +31,8 @@
#define FRAME_TIME_MS 41 // roughly 24 fps
#define PWM_FREQ_HZ 150000
// constants
// LUT for converting NTC readings to degrees kelvin
// Nominal: 1kOhm, Beta: 3380, Step: 64
@ -279,6 +281,68 @@ static inline bool adc_injection_conversion() {
return true;
}
// mask for the CCxP bits
// when set PWM outputs are held HIGH by default and pulled LOW
// when zero PWM outputs are held LOW by default and pulled HIGH
// #define TIM3_DEFAULT 0xff
#define TIM3_DEFAULT 0x00
static inline void setup_pwm(void)
{
// Enable TIM3 clock
RCC->APB1PCENR |= RCC_APB1Periph_TIM3;
// Since TIM3 is enabled with TIM3->SMCFGR.SMS = 0b000 (default value) the
// clock source is the internal clock
// The internal clock goes through the HBB prescaler RCC->CFGR0.HPRE which
// by default is disabled
// Reset TIM3 to init all regs
RCC->APB1PRSTR |= RCC_APB1Periph_TIM3;
RCC->APB1PRSTR &= ~RCC_APB1Periph_TIM3;
// set TIM3 clock prescaler divider
TIM3->PSC = 0x0000; // no prescaler
// set PWM total cycle width
static_assert((FUNCONF_SYSTEM_CORE_CLOCK / PWM_FREQ_HZ - 1) < 0xffff, "PWM_FREQ_HZ too low for TIM3");
TIM3->ATRLR = FUNCONF_SYSTEM_CORE_CLOCK / PWM_FREQ_HZ - 1;
// for channel 1 let CCxS stay 00 (output), set OC1M to 110 (PWM 1)
// enabling preload (OC1PE) causes the new pulse width in compare capture
// register only to come into effect when UG bit in SWEVGR is set
// (= initiate update) (auto-clears)
TIM3->CHCTLR1 |= TIM_OC1M_2 | TIM_OC1M_1 | TIM_OC1PE;
// Enable channel 1 output (PA6)
TIM3->CCER |= TIM_CC1E | ( TIM_CC1P & TIM3_DEFAULT );
// CTLR1: default is up, events generated, edge align
// enable auto-reload of preload
TIM3->CTLR1 |= TIM_ARPE;
}
static inline void pwm_on(void)
{
// initialize counter
TIM3->SWEVGR |= TIM_UG;
// Enable TIM3
TIM3->CTLR1 |= TIM_CEN;
}
static inline void pwm_off(void)
{
// Disable TIM3
TIM3->CTLR1 &= ~TIM_CEN;
TIM3->CH1CVR = 0;
}
static inline void pwm_set(uint16_t pulse_width)
{
TIM3->CH1CVR = pulse_width;
}
__attribute__((noreturn)) int main(void)
{
@ -303,7 +367,7 @@ __attribute__((noreturn)) int main(void)
funPinMode(PIN_12V, GPIO_CFGLR_OUT_10Mhz_PP);
funDigitalWrite(PIN_12V, 0);
funPinMode(PIN_HEATER, GPIO_CFGLR_OUT_10Mhz_PP);
funPinMode(PIN_HEATER, GPIO_CFGLR_OUT_10Mhz_AF_PP);
funDigitalWrite(PIN_HEATER, 0);
funPinMode(PIN_DISP_RST, GPIO_CFGLR_OUT_10Mhz_PP);
funDigitalWrite(PIN_DISP_RST, 1); // start with display disabled
@ -314,6 +378,9 @@ __attribute__((noreturn)) int main(void)
funDigitalWrite(PIN_ENC_B, 1); // specify pull-up
funPinMode(PIN_BTN, GPIO_CFGLR_IN_FLOAT);
setup_pwm();
pwm_off();
setup_i2c();
// Configure the IO as an interrupt.
@ -392,6 +459,11 @@ __attribute__((noreturn)) int main(void)
}
}
if (idx_9v >= 0) {
USBPD_SelectPDO(idx_9v, 0);
Delay_Ms(200);
}
for (;;) {
static uint16_t tip_mv, vbus_mv, current_ma;
static int16_t temp_k;
@ -408,6 +480,20 @@ __attribute__((noreturn)) int main(void)
tip_mv = U16_FP_EMA_K4(tip_mv, (u32)(injection_results[0]*VCC_MV)/4096);
}
static bool pwm = false;
if (funDigitalRead(PIN_BTN) == 0) {
if (!pwm) {
funDigitalWrite(PIN_12V, 1);
pwm_on();
pwm = true;
pwm_set(100);
}
} else {
funDigitalWrite(PIN_12V, 0);
pwm_off();
pwm = false;
}
u8g2_ClearBuffer(u8g2);
u8g2_SetBitmapMode(u8g2, 1);
u8g2_SetFontMode(u8g2, 1);
@ -415,32 +501,40 @@ __attribute__((noreturn)) int main(void)
#define x_off 0
#define y_off 8
static bool mode = true;
if (mode) {
// if (mode) {
u8g2_DrawStr(u8g2, x_off+0, y_off+7, "TIP:");
u8g2_DrawStr(u8g2, x_off+20, y_off+7, u8x8_u16toa(tip_mv, 4));
u8g2_DrawStr(u8g2, x_off+0, y_off+15, "VBUS:");
u8g2_DrawStr(u8g2, x_off+25, y_off+15, u8x8_u16toa(vbus_mv, 4));
u8g2_DrawStr(u8g2, x_off+51, y_off+7, "TEMP:");
u8g2_DrawStr(u8g2, x_off+75, y_off+7, u8x8_u16toa(temp_k, 2));
u8g2_DrawStr(u8g2, x_off+51, y_off+15, "V:");
u8g2_DrawStr(u8g2, x_off+60, y_off+15, u8x8_u16toa(max_v, 2));
} else {
static int16_t ax, ay, az;
sc7a20_get_readings(&ax, &ay, &az);
u8g2_DrawStr(u8g2, x_off+0, y_off+7, ax > 0 ? "AX:+" : "AX:-");
u8g2_DrawStr(u8g2, x_off+20, y_off+7, u8x8_u16toa(ax > 0 ? ax : -ax, 5));
u8g2_DrawStr(u8g2, x_off+0, y_off+15, ay > 0 ? "AY:+" : "AY:-");
u8g2_DrawStr(u8g2, x_off+20, y_off+15, u8x8_u16toa(ay > 0 ? ay : -ay, 5));
u8g2_DrawStr(u8g2, x_off+50, y_off+7, az > 0 ? "AZ:+" : "AZ:-");
u8g2_DrawStr(u8g2, x_off+70, y_off+7, u8x8_u16toa(az > 0 ? az : -az, 5));
//u8g2_DrawStr(u8g2, x_off+51, y_off+15, "V:");
//u8g2_DrawStr(u8g2, x_off+60, y_off+15, u8x8_u16toa(max_v, 2));
u8g2_DrawStr(u8g2, x_off+50, y_off+15, "CURR:");
u8g2_DrawStr(u8g2, x_off+75, y_off+15, u8x8_u16toa(current_ma, 4));
// } else {
// static int16_t ax, ay, az;
// sc7a20_get_readings(&ax, &ay, &az);
// u8g2_DrawStr(u8g2, x_off+0, y_off+7, ax > 0 ? "AX:+" : "AX:-");
// u8g2_DrawStr(u8g2, x_off+20, y_off+7, u8x8_u16toa(ax > 0 ? ax : -ax, 5));
// u8g2_DrawStr(u8g2, x_off+0, y_off+15, ay > 0 ? "AY:+" : "AY:-");
// u8g2_DrawStr(u8g2, x_off+20, y_off+15, u8x8_u16toa(ay > 0 ? ay : -ay, 5));
// u8g2_DrawStr(u8g2, x_off+50, y_off+7, az > 0 ? "AZ:+" : "AZ:-");
// u8g2_DrawStr(u8g2, x_off+70, y_off+7, u8x8_u16toa(az > 0 ? az : -az, 5));
// }
if (pwm) {
u8g2_DrawBox(u8g2, x_off+92, y_off+0, 4, 4);
}
u8g2_SendBuffer(u8g2);
/*
if (idx_9v != -1 && funDigitalRead(PIN_BTN) == 0) {
USBPD_SelectPDO(idx_9v, 0);
Delay_Ms(200);
}
*/
if (encoder != 0) {
mode = !mode;
encoder = 0;