From ea37906c9e1f243c86714055832c7f67a7858b56 Mon Sep 17 00:00:00 2001
From: eeucalyptus <dev@eeucalyptus.net>
Date: Tue, 25 Jul 2023 22:09:21 +0200
Subject: [PATCH] Implement example project for adc with dma and fixed sampling
rate
---
examples/adc_fixed_fs/Makefile | 10 ++
examples/adc_fixed_fs/adc_fixed_fs.c | 146 +++++++++++++++++++++++++++
examples/adc_fixed_fs/funconfig.h | 11 ++
3 files changed, 167 insertions(+)
create mode 100644 examples/adc_fixed_fs/Makefile
create mode 100644 examples/adc_fixed_fs/adc_fixed_fs.c
create mode 100644 examples/adc_fixed_fs/funconfig.h
diff --git a/examples/adc_fixed_fs/Makefile b/examples/adc_fixed_fs/Makefile
new file mode 100644
index 0000000..83283cb
--- /dev/null
+++ b/examples/adc_fixed_fs/Makefile
@@ -0,0 +1,10 @@
+all : flash
+
+TARGET:=adc_fixed_fs
+
+include ../../ch32v003fun/ch32v003fun.mk
+
+flash : cv_flash
+clean : cv_clean
+
+
diff --git a/examples/adc_fixed_fs/adc_fixed_fs.c b/examples/adc_fixed_fs/adc_fixed_fs.c
new file mode 100644
index 0000000..283e555
--- /dev/null
+++ b/examples/adc_fixed_fs/adc_fixed_fs.c
@@ -0,0 +1,146 @@
+/*
+ * Example for using ADC with DMA and timer for fixed sampling rate
+ * by eeucalyptus
+ */
+
+#include "ch32v003fun.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+#define BUFFER_LENGTH 128
+volatile uint16_t buffer[2][BUFFER_LENGTH] = {0};
+volatile uint32_t current_write_buffer = 0;
+#define current_read_buffer (1-current_write_buffer)
+
+void init_dma()
+{
+ // Start DMA clock
+ RCC->AHBPCENR |= RCC_AHBPeriph_DMA1;
+
+ // Setup DMA Channel 1 (adc triggered) as reading, 16-bit, linear buffer
+ DMA1_Channel1->CFGR = DMA_DIR_PeripheralSRC |
+ DMA_MemoryInc_Enable |
+ DMA_PeripheralDataSize_HalfWord |
+ DMA_MemoryDataSize_HalfWord;
+ // No of samples to get before irq
+ DMA1_Channel1->CNTR = BUFFER_LENGTH;
+ // Source
+ DMA1_Channel1->PADDR = (uint32_t)&ADC1->RDATAR;
+ // Destination
+ DMA1_Channel1->MADDR = (uint32_t)buffer[current_write_buffer];
+
+ // Enable IRQ and DMA channel
+ NVIC_EnableIRQ(DMA1_Channel1_IRQn);
+ DMA1_Channel1->CFGR |= DMA_IT_TC | DMA_CFGR1_EN;
+}
+
+void init_timer() {
+ // TIMER
+ printf("Initializing timer...\r\n");
+ RCC->APB2PCENR |= RCC_APB2Periph_TIM1;
+ TIM1->CTLR1 |= TIM_CounterMode_Up | TIM_CKD_DIV1;
+ TIM1->CTLR2 = TIM_MMS_1;
+ TIM1->ATRLR = 1000;
+ TIM1->PSC = 10-1;
+ TIM1->RPTCR = 0;
+ TIM1->SWEVGR = TIM_PSCReloadMode_Immediate;
+
+ NVIC_EnableIRQ(TIM1_UP_IRQn);
+ TIM1->INTFR = ~TIM_FLAG_Update;
+ TIM1->DMAINTENR |= TIM_IT_Update;
+ TIM1->CTLR1 |= TIM_CEN;
+}
+
+void init_adc() {
+ printf("Initializing ADC...\r\n");
+
+ RCC->APB2PCENR |= RCC_APB2Periph_GPIOC;
+ GPIOC->CFGLR &= ~(0xf<<(4*4)); // CNF = 00: Analog, MODE = 00: Input
+
+ RCC->APB2PCENR |= RCC_APB2Periph_ADC1;
+
+ // Reset the ADC to init all regs
+ RCC->APB2PRSTR |= RCC_APB2Periph_ADC1;
+ RCC->APB2PRSTR &= ~RCC_APB2Periph_ADC1;
+
+ // ADCCLK = 24 MHz => RCC_ADCPRE divide by 2
+ RCC->CFGR0 &= ~RCC_ADCPRE; // Clear out the bis in case they were set
+ RCC->CFGR0 |= RCC_ADCPRE_DIV2; // set it to 010xx for /2.
+
+ // Keep CALVOL register with initial value
+ ADC1->CTLR1 |= ADC_ExternalTrigConv_T1_TRGO;
+ ADC1->CTLR2 = ADC_ADON | ADC_DMA | ADC_EXTTRIG;
+
+ // Possible times: 0->3,1->9,2->15,3->30,4->43,5->57,6->73,7->241 cycles
+ ADC1->SAMPTR2 = 0/*3 cycles*/ << (3/*offset per channel*/ * 2/*channel*/);
+
+ // Set sequencer to channel 2 only
+ ADC1->RSQR3 = 2;
+
+ // Calibrate
+ printf("Calibrating ADC...\r\n");
+ ADC1->CTLR2 |= ADC_RSTCAL;
+ while(ADC1->CTLR2 & ADC_RSTCAL);
+ ADC1->CTLR2 |= ADC_CAL;
+ while(ADC1->CTLR2 & ADC_CAL);
+
+ // Interrupt will no work as long as DMA is on. why? does DMA clear the flag so fast?
+// ADC1->STATR = ~ADC_FLAG_EOC;
+// ADC1->CTLR1 |= ADC_IT_EOC;
+// NVIC_EnableIRQ(ADC_IRQn);
+
+}
+
+void TIM1_UP_IRQHandler(void) __attribute__((interrupt));
+void TIM1_UP_IRQHandler() {
+ if(TIM1->INTFR & TIM_FLAG_Update) {
+ TIM1->INTFR = ~TIM_FLAG_Update;
+ //printf("TIMER ISR!...\r\n");
+ }
+}
+
+void ADC1_IRQHandler(void) __attribute__((interrupt));
+void ADC1_IRQHandler() {
+ if(ADC1->STATR & ADC_FLAG_EOC) {
+ ADC1->STATR = ~ADC_FLAG_EOC;
+ int adcraw = ADC1->RDATAR;
+ //printf("ADC ISR! in=%d\r\n", adcraw);
+ }
+}
+
+void DMA1_Channel1_IRQHandler(void) __attribute__((interrupt));
+void DMA1_Channel1_IRQHandler()
+{
+ if(DMA1->INTFR & DMA1_FLAG_TC1)
+ {
+ DMA1->INTFCR = DMA_CTCIF1;
+// printf("DMA ISR!\r\n");
+ current_write_buffer = current_read_buffer;
+ init_dma();
+ }
+}
+
+volatile int test = 0;
+
+int main() {
+ SystemInit();
+
+ init_dma();
+ init_adc();
+ init_timer();
+
+ test = atoi("123");
+
+ int last_handled_buffer = current_read_buffer;
+ while(1) {
+ if(last_handled_buffer != current_read_buffer) {
+ last_handled_buffer = current_read_buffer;
+ for(int i = 0; i < BUFFER_LENGTH; i++) {
+ while( !(USART1->STATR & USART_FLAG_TC));
+ USART1->DATAR = (const char)((buffer[current_read_buffer][i])&0xff);
+ while( !(USART1->STATR & USART_FLAG_TC));
+ USART1->DATAR = (const char)((buffer[current_read_buffer][i])>>8);
+ }
+ }
+ }
+}
diff --git a/examples/adc_fixed_fs/funconfig.h b/examples/adc_fixed_fs/funconfig.h
new file mode 100644
index 0000000..2cd0523
--- /dev/null
+++ b/examples/adc_fixed_fs/funconfig.h
@@ -0,0 +1,11 @@
+#ifndef _FUNCONFIG_H
+#define _FUNCONFIG_H
+
+#define CH32V003 1
+#define FUNCONF_USE_HSE 1
+#define FUNCONF_USE_PLL 1 // Do not use built-in 2x PLL
+#define FUNCONF_USE_UARTPRINTF 1
+#define FUNCONF_UART_PRINTF_BAUD 115200
+
+#endif
+
--
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