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-rw-r--r--src/lib/usart.c345
1 files changed, 0 insertions, 345 deletions
diff --git a/src/lib/usart.c b/src/lib/usart.c
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--- a/src/lib/usart.c
+++ /dev/null
@@ -1,345 +0,0 @@
-/* *****************************************************************************
- * 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/>.
- *
- * Created: 12/18/09 02:38:26
- * Copyright (c) 2009 Perry L. Hung. All rights reserved.
- *
- * ****************************************************************************/
-
-/**
- * @file usart.c
- *
- * @brief USART control routines
- */
-
-#include "libmaple.h"
-#include "stm32f10x_rcc.h"
-#include "usart.h"
-#include "nvic.h"
-
-#define USART1_BASE 0x40013800
-#define USART2_BASE 0x40004400
-#define USART3_BASE 0x40004800
-
-#define USART_UE BIT(13)
-#define USART_M BIT(12)
-#define USART_TE BIT(3)
-#define USART_RE BIT(2)
-#define USART_RXNEIE BIT(5) // read data register not empty interrupt enable
-#define USART_TXE BIT(7)
-#define USART_TC BIT(6)
-
-#define USART_STOP_BITS_1 BIT_MASK_SHIFT(0b0, 12)
-#define USART_STOP_BITS_05 BIT_MASK_SHIFT(0b01, 12)
-#define USART_STOP_BITS_2 BIT_MASK_SHIFT(0b02, 12)
-#define USART_STOP_BITS_15 BIT_MASK_SHIFT(0b02, 12)
-
-#define USART1_CLK 72000000UL
-#define USART2_CLK 36000000UL
-#define USART3_CLK 36000000UL
-
-#define USART_RECV_BUF_SIZE 64
-
-/* Ring buffer notes:
- * The buffer is empty when head == tail.
- * The buffer is full when the head is one byte in front of the tail
- * The total buffer size must be a power of two
- * Note, one byte is necessarily left free with this scheme */
-typedef struct usart_ring_buf {
- uint32 head;
- uint32 tail;
- uint8 buf[USART_RECV_BUF_SIZE];
-} usart_ring_buf;
-
-static usart_ring_buf ring_buf1;
-static usart_ring_buf ring_buf2;
-static usart_ring_buf ring_buf3;
-
-typedef struct usart_port {
- volatile uint32 SR; // Status register
- volatile uint32 DR; // Data register
- volatile uint32 BRR; // Baud rate register
- volatile uint32 CR1; // Control register 1
- volatile uint32 CR2; // Control register 2
- volatile uint32 CR3; // Control register 3
- volatile uint32 GTPR; // Guard time and prescaler register
-} usart_port;
-
-void USART1_IRQHandler(void) {
- /* Read the data */
- ring_buf1.buf[ring_buf1.tail++] = (uint8_t)(((usart_port*)(USART1_BASE))->DR);
- ring_buf1.tail %= USART_RECV_BUF_SIZE;
-}
-
-/* Don't overrun your buffer, seriously */
-void USART2_IRQHandler(void) {
- /* Read the data */
- ring_buf2.buf[ring_buf2.tail++] = (uint8_t)(((usart_port*)(USART2_BASE))->DR);
- ring_buf2.tail %= USART_RECV_BUF_SIZE;
-}
-/* Don't overrun your buffer, seriously */
-void USART3_IRQHandler(void) {
- /* Read the data */
- ring_buf3.buf[ring_buf3.tail++] = (uint8_t)(((usart_port*)(USART3_BASE))->DR);
- ring_buf3.tail %= USART_RECV_BUF_SIZE;
-}
-
-/**
- * @brief Enable a USART in single buffer transmission mode, multibuffer
- * receiver mode.
- *
- * @param usart_num USART to be initialized
- * @param baud Baud rate to be set at
- * @param recvBuf buf buffer for receiver
- * @param len size of recvBuf
- *
- * @sideeffect Turns on the specified USART
- */
-void usart_init(uint8 usart_num, uint32 baud) {
- ASSERT((usart_num <= NR_USARTS) && (usart_num > 0));
- ASSERT(baud && (baud < USART_MAX_BAUD));
-
- usart_port *port;
- usart_ring_buf *ring_buf;
-
- uint32 clk_speed;
- uint32 integer_part;
- uint32 fractional_part;
- uint32 tmp;
-
- switch (usart_num) {
- case 1:
- port = (usart_port*)USART1_BASE;
- ring_buf = &ring_buf1;
- clk_speed = USART1_CLK;
- RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
- REG_SET(NVIC_ISER1, BIT(5));
- break;
- case 2:
- port = (usart_port*)USART2_BASE;
- ring_buf = &ring_buf2;
- clk_speed = USART2_CLK;
- RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
- REG_SET(NVIC_ISER1, BIT(6));
- break;
- case 3:
- port = (usart_port*)USART3_BASE;
- ring_buf = &ring_buf3;
- clk_speed = USART3_CLK;
- RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);
- REG_SET(NVIC_ISER1, BIT(7));
- break;
- default:
- /* should never get here */
- ASSERT(0);
- }
-
- /* Initialize ring buffer */
- ring_buf->head = 0;
- ring_buf->tail = 0;
-
- /* Set baud rate */
- integer_part = ((25 * clk_speed) / (4 * baud));
- tmp = (integer_part / 100) << 4;
-
- fractional_part = integer_part - (100 * (tmp >> 4));
- tmp |= (((fractional_part * 16) + 50) / 100) & ((uint8)0x0F);
-
- port->BRR = (uint16_t)tmp;
-
- port->CR1 = USART_TE | // transmitter enable
- USART_RE | // receiver enable
- USART_RXNEIE; // receive interrupt enable
-
-
- /* Enable the USART and set mode to 8n1 */
- port->CR1 |= USART_UE;
-}
-
-
-/**
- * @brief Turn off a USART.
- *
- * @param USART to be disabled
- *
- * @sideeffect Turns off the specified USART
- */
-void usart_disable(uint8 usart_num) {
- ASSERT((usart_num <= NR_USARTS) && (usart_num > 0));
- usart_port *port;
-
- switch (usart_num) {
- case 1:
- port = (usart_port*)USART1_BASE;
- break;
- case 2:
- port = (usart_port*)USART2_BASE;
- break;
- case 3:
- port = (usart_port*)USART3_BASE;
- break;
- default:
- /* should never get here */
- ASSERT(0);
- }
-
- /* Is this usart enabled? */
- if (!(port->SR & USART_UE))
- return;
-
- /* TC bit must be high before disabling the usart */
- while ((port->SR & USART_TC) == 0)
- ;
-
- /* Disable UE */
- port->CR1 = 0;
-}
-
-
-/**
- * @brief Print a null terminated string to the specified USART
- *
- * @param[in] usart_num USART to send on
- * @param[in] str String to send
- */
-void usart_putstr(uint8 usart_num, const char* str) {
- ASSERT((usart_num <= NR_USARTS) && (usart_num > 0));
- char ch;
-
- while((ch = *(str++)) != '\0') {
- usart_putc(usart_num, ch);
- }
-}
-
-/**
- * @brief Print an unsigned integer to the specified usart
- *
- * @param[in] usart_num usart to send on
- * @param[in] val number to print
- */
-void usart_putudec(uint8 usart_num, uint32 val) {
- ASSERT((usart_num <= NR_USARTS) && (usart_num > 0));
- char digits[12];
- int i;
-
- i = 0;
- do {
- digits[i++] = val % 10 + '0';
- val /= 10;
- } while (val > 0);
- while (--i >= 0) {
- usart_putc(usart_num, digits[i]);
- }
-
-}
-
-
-/**
- * @brief Return one character from the receive buffer. Assumes
- * that there is data available.
- *
- * @param[in] usart_num number of the usart to read from
- *
- * @return character from ring buffer
- *
- * @sideeffect may update the head pointer of the recv buffer
- */
-uint8 usart_getc(uint8 usart_num) {
- uint8 ch;
- usart_ring_buf *rb;
-
- switch (usart_num) {
- case 1:
- rb = &ring_buf1;
- break;
- case 2:
- rb = &ring_buf2;
- break;
- case 3:
- rb = &ring_buf3;
- break;
- default:
- ASSERT(0);
- }
-
- /* Make sure there's actually data to be read */
- ASSERT(rb->head != rb->tail);
-
- /* Read the data and check for wraparound */
- ch = rb->buf[rb->head++];
- rb->head %= USART_RECV_BUF_SIZE;
-
- return ch;
-}
-
-uint32 usart_data_available(uint8 usart_num) {
- usart_ring_buf *rb;
-
- switch (usart_num) {
- case 1:
- rb = &ring_buf1;
- break;
- case 2:
- rb = &ring_buf2;
- break;
- case 3:
- rb = &ring_buf3;
- break;
- default:
- ASSERT(0);
- }
-
- return rb->tail - rb->head;
-}
-
-
-
-/**
- * @brief Output a byte out the uart
- *
- * @param[in] usart_num usart number to output on
- * @param[in] byte byte to send
- *
- */
-void usart_putc(uint8 usart_num, uint8 byte) {
- ASSERT((usart_num <= NR_USARTS) && (usart_num > 0));
- usart_port *port;
-
- switch (usart_num) {
- case 1:
- port = (usart_port*)USART1_BASE;
- break;
- case 2:
- port = (usart_port*)USART2_BASE;
- break;
- case 3:
- port = (usart_port*)USART3_BASE;
- break;
- default:
- /* Should never get here */
- ASSERT(0);
- }
-
-// if (ch == '\n') {
-// usart_putc(usart_num, '\r');
-// }
-
- port->DR = byte;
-
- /* Wait for transmission to complete */
- while ((port->SR & USART_TXE) == 0)
- ;
-}
-
-
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