8seg/center_fw/main.c
2019-04-17 16:32:43 +09:00

194 lines
6 KiB
C

/* Megumin LED display firmware
* Copyright (C) 2018 Sebastian Götte <code@jaseg.net>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "global.h"
#include "adc.h"
#include "8seg_protocol.h"
#include "transmit.h"
volatile unsigned int sys_time = 0;
volatile unsigned int sys_time_seconds = 0;
uint16_t jitter_meas_avg_ns = 0;
void TIM1_BRK_UP_TRG_COM_Handler() {
TIM1->SR &= ~TIM_SR_UIF_Msk;
}
void set_drv_gpios(uint8_t val) {
int a=!!(val&1), b=!!(val&2), c=!!(val&4), d=!!(val&8);
GPIOA->BSRR = ((!a<<3 | !b<<7 | c<<6 | d<<4)<<16) | (a<<3 | b<<7 | !c<<6 | !d<<4);
}
uint8_t out_state = 0x01;
void set_outputs(uint8_t val[8]) {
/* TODO implement BCM for digital brightness control */
int x = 0;
for (int i=0; i<8; i++)
if (val[i] > 127)
x |= 1<<i;
out_state = x;
}
void set_outputs_binary(int mask, int global_brightness) {
uint8_t val[8];
for (int i=0; i<8; i++)
val[i] = (mask & (1<<i)) ? global_brightness : 0;
set_outputs(val);
}
void set_load(bool load) {
GPIOA->BSRR = (1<<2) << (load ? 0 : 16);
}
void blank(void) {
set_drv_gpios(0);
}
volatile int bit; /* FIXME */
void unblank_low(void) {
if (backchannel_frame) { /* Set from protocol.c */
if (tx_next_bit() == 1)
set_load(1);
else /* 0; but also TX_IDLE */
set_load(0);
} else {
if (bit)
set_drv_gpios(out_state & 0xf);
else
set_drv_gpios(out_state >> 4);
}
}
void TIM3_IRQHandler(void) {
GPIOA->BSRR = 1<<10; /* debug */
if (TIM3->SR & TIM_SR_UIF)
unblank_low();
else
blank();
TIM3->SR = 0;
GPIOA->BRR = 1<<10; /* debug */
}
int main(void) {
RCC->CR |= RCC_CR_HSEON;
while (!(RCC->CR&RCC_CR_HSERDY));
RCC->CFGR &= ~RCC_CFGR_PLLMUL_Msk & ~RCC_CFGR_SW_Msk & ~RCC_CFGR_PPRE_Msk & ~RCC_CFGR_HPRE_Msk;
RCC->CFGR |= ((6-2)<<RCC_CFGR_PLLMUL_Pos) | RCC_CFGR_PLLSRC_HSE_PREDIV; /* PLL x6 -> 48.0MHz */
RCC->CR |= RCC_CR_PLLON;
while (!(RCC->CR&RCC_CR_PLLRDY));
RCC->CFGR |= (2<<RCC_CFGR_SW_Pos);
SystemCoreClockUpdate();
//SysTick_Config(SystemCoreClock/1000); /* 1ms interval */
/* Turn on lots of neat things */
RCC->AHBENR |= RCC_AHBENR_DMAEN | RCC_AHBENR_GPIOAEN | RCC_AHBENR_FLITFEN;
RCC->APB2ENR |= RCC_APB2ENR_SYSCFGEN | RCC_APB2ENR_ADCEN| RCC_APB2ENR_DBGMCUEN | RCC_APB2ENR_TIM1EN | RCC_APB2ENR_TIM1EN;;
RCC->APB1ENR |= RCC_APB1ENR_TIM3EN;
/* TIM3 foo */
TIM3->CCMR2 = (6<<TIM_CCMR2_OC4M_Pos); /* PWM Mode 1 to get a clean trigger signal */
TIM3->CCER = TIM_CCER_CC4E; /* Enable capture/compare unit 4 connected to ADC */
TIM3->PSC = 48-1; /* 48MHz -> 1MHz */
TIM3->CCR4 = 170-1; /* CC4 is ADC trigger, fire 30us before end of cycle. */
TIM3->ARR = 200-1; /* 1MHz -> 5kHz */
TIM3->DIER |= TIM_DIER_UIE | TIM_DIER_CC4IE;
TIM3->CR1 |= TIM_CR1_CEN;
NVIC_EnableIRQ(TIM3_IRQn);
NVIC_SetPriority(TIM3_IRQn, 3<<5);
GPIOA->MODER |=
(0<<GPIO_MODER_MODER0_Pos) /* PA0 - Vmeas_A to ADC */
| (0<<GPIO_MODER_MODER1_Pos) /* PA1 - Vmeas_B to ADC */
| (1<<GPIO_MODER_MODER2_Pos) /* PA2 - LOAD */
| (1<<GPIO_MODER_MODER3_Pos) /* PA3 - CH0 */
| (1<<GPIO_MODER_MODER4_Pos) /* PA4 - CH3 */
| (1<<GPIO_MODER_MODER5_Pos) /* PA5 - TP1 */
| (1<<GPIO_MODER_MODER6_Pos) /* PA6 - CH2 */
| (1<<GPIO_MODER_MODER7_Pos) /* PA7 - CH1 */
| (1<<GPIO_MODER_MODER9_Pos) /* PA9 - TP2 */
| (1<<GPIO_MODER_MODER10_Pos);/* PA10 - TP3 */
/* Set shift register IO GPIO output speed */
GPIOA->OSPEEDR |=
(2<<GPIO_OSPEEDR_OSPEEDR2_Pos) /* LOAD */
| (2<<GPIO_OSPEEDR_OSPEEDR3_Pos) /* CH0 */
| (2<<GPIO_OSPEEDR_OSPEEDR4_Pos) /* CH3 */
| (2<<GPIO_OSPEEDR_OSPEEDR6_Pos) /* CH2 */
| (2<<GPIO_OSPEEDR_OSPEEDR7_Pos); /* CH1 */
set_drv_gpios(0);
protocol_init();
uint32_t jitter_meas_sum = 0, jitter_meas_cnt = 0;
while (42) {
int new = GPIOA->IDR & (1<<0); /* Sample current polarity */
if (new != bit) { /* Zero-crossing detected */
bit = new;
/* Store old counter value for jitter measurement. Let it overflow to handle negative offsets. */
int16_t cnt = (int16_t)TIM3->CNT;
/* Re-initialize the counter to align it with the signal edge */
TIM3->EGR |= TIM_EGR_UG;
/* Unblank since the update interrupt will not fire this time */
unblank_low();
/* Don't handle overflow of _sum here since this value is only for monitoring anyway */
jitter_meas_sum += (cnt >= 0) ? cnt : -cnt;
if (++jitter_meas_cnt == 4000) { /* One measurement roughly every 800ms */
/* Divide aggregate over 4000 us-resolution measurements by 4 -> ns-resolution average */
uint32_t divided = jitter_meas_sum>>2;
jitter_meas_avg_ns = (divided < UINT16_MAX) ? divided : UINT16_MAX;
}
}
/* idle */
}
}
void NMI_Handler(void) {
asm volatile ("bkpt");
}
void HardFault_Handler(void) __attribute__((naked));
void HardFault_Handler() {
asm volatile ("bkpt");
}
void SVC_Handler(void) {
asm volatile ("bkpt");
}
void PendSV_Handler(void) {
asm volatile ("bkpt");
}
void SysTick_Handler(void) {
static int n = 0;
sys_time++;
if (n++ == 1000) {
n = 0;
sys_time_seconds++;
}
}