dosimeter/stm32workspace/dosim-v1/Core/Src/uartio.c

/*
 * uartio.c
 *
 *  Created on: Jan 21, 2022
 *      Author: radioman
 */

#include "main.h"
#include "uartio.h"
#include <string.h>

static uint8_t uart_rx_buffer[UART_RX_BUF_SIZE];
static uint8_t uart_tx_buffer[UART_TX_BUF_SIZE];

static uint32_t rd_ptr;
static uint8_t tx_cplt = 1;

void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart)
{
	tx_cplt = 1;
}

void UARTIO_Init(UART_HandleTypeDef *huart)
{
	HAL_UART_Receive_DMA(huart, uart_rx_buffer, UART_RX_BUF_SIZE);
	rd_ptr = 0;
}

uint32_t UARTIO_DataAvail(UART_HandleTypeDef *huart)
{
	if((UART_RX_BUF_SIZE - huart->hdmarx->Instance->CNDTR) >= rd_ptr)
		return (UART_RX_BUF_SIZE - huart->hdmarx->Instance->CNDTR) - rd_ptr;
	else
		return (2 * UART_RX_BUF_SIZE) - rd_ptr - huart->hdmarx->Instance->CNDTR;

}

uint32_t UARTIO_Receive(UART_HandleTypeDef *huart, uint8_t *buf)
{
	uint32_t dma_ptr = (UART_RX_BUF_SIZE - huart->hdmarx->Instance->CNDTR);
	if(dma_ptr > rd_ptr)
	{
		uint32_t data_avail = dma_ptr - rd_ptr;
		memcpy(&buf[0], &uart_rx_buffer[rd_ptr], data_avail);
		rd_ptr = dma_ptr;
		return (data_avail);
	}
	else if(dma_ptr < rd_ptr)
	{
		uint32_t blk1_sz = UART_RX_BUF_SIZE - rd_ptr;
		memcpy(&buf[0], &uart_rx_buffer[rd_ptr], blk1_sz);
		memcpy(&buf[blk1_sz], &uart_rx_buffer[0], dma_ptr);
		rd_ptr = dma_ptr;
		return (blk1_sz + dma_ptr);
	}
	else
	{
		return 0;
	}
}

uint32_t UARTIO_Transmit(UART_HandleTypeDef *huart, uint8_t *buf, uint32_t len)
{
	memcpy(uart_tx_buffer, buf, len);
	while(!tx_cplt);
	HAL_UART_Transmit_DMA(huart, uart_tx_buffer, len);
	tx_cplt = 0;
	return len;
}