restructuring

F0:F030,F042,F072/USBHID/usart.c

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+/*
+ * usart.c
+ *
+ * Copyright 2017 Edward V. Emelianoff <eddy@sao.ru, edward.emelianoff@gmail.com>
+ *
+ * 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 2 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+#include "stm32f0.h"
+#include "hardware.h"
+#include "usart.h"
+#include <string.h>
+
+extern volatile uint32_t Tms;
+static volatile int idatalen[2] = {0,0}; // received data line length (including '\n')
+static volatile int odatalen[2] = {0,0};
+
+volatile int linerdy = 0,        // received data ready
+    dlen = 0,           // length of data (including '\n') in current buffer
+    bufovr = 0,         // input buffer overfull
+    txrdy = 1           // transmission done
+;
+
+
+int rbufno = 0, tbufno = 0; // current rbuf/tbuf numbers
+static char rbuf[2][UARTBUFSZI], tbuf[2][UARTBUFSZO]; // receive & transmit buffers
+static char *recvdata = NULL;
+
+/**
+ * return length of received data (without trailing zero
+ */
+int usart_getline(char **line){
+    if(bufovr){
+        bufovr = 0;
+        linerdy = 0;
+        return 0;
+    }
+    *line = recvdata;
+    linerdy = 0;
+    return dlen;
+}
+
+// transmit current tbuf and swap buffers
+void transmit_tbuf(){
+    uint32_t tmout = 16000000;
+    while(!txrdy){if(--tmout == 0) break;}; // wait for previos buffer transmission
+    register int l = odatalen[tbufno];
+    if(!l) return;
+    txrdy = 0;
+    odatalen[tbufno] = 0;
+    USARTDMA->CCR &= ~DMA_CCR_EN;
+    USARTDMA->CMAR = (uint32_t) tbuf[tbufno]; // mem
+    USARTDMA->CNDTR = l;
+    USARTDMA->CCR |= DMA_CCR_EN;
+    tbufno = !tbufno;
+}
+
+void usart_putchar(const char ch){
+    if(odatalen[tbufno] == UARTBUFSZO) transmit_tbuf();
+    tbuf[tbufno][odatalen[tbufno]++] = ch;
+}
+
+void usart_send(const char *str){
+    uint32_t x = 512;
+    while(*str && --x){
+        if(odatalen[tbufno] == UARTBUFSZO) transmit_tbuf();
+        tbuf[tbufno][odatalen[tbufno]++] = *str++;
+    }
+}
+
+void usart_sendn(const char *str, uint8_t L){
+    for(uint8_t i = 0; i < L; ++i){
+        if(odatalen[tbufno] == UARTBUFSZO) transmit_tbuf();
+        tbuf[tbufno][odatalen[tbufno]++] = *str++;
+    }
+}
+
+void newline(){
+    usart_putchar('\n');
+    transmit_tbuf();
+}
+
+
+void usart_setup(){
+    uint32_t tmout = 16000000;
+// Nucleo's USART2 connected to VCP proxy of st-link
+#if USARTNUM == 2
+    // setup pins: PA2 (Tx - AF1), PA15 (Rx - AF1)
+    // AF mode (AF1)
+    GPIOA->MODER = (GPIOA->MODER & ~(GPIO_MODER_MODER2|GPIO_MODER_MODER15))\
+                | (GPIO_MODER_MODER2_AF | GPIO_MODER_MODER15_AF);
+    GPIOA->AFR[0] = (GPIOA->AFR[0] &~GPIO_AFRH_AFRH2) | 1 << (2 * 4); // PA2
+    GPIOA->AFR[1] = (GPIOA->AFR[1] &~GPIO_AFRH_AFRH7) | 1 << (7 * 4); // PA15
+    RCC->APB1ENR |= RCC_APB1ENR_USART2EN; // clock
+// USART1 of main board
+#elif USARTNUM == 1
+    // PA9 - Tx, PA10 - Rx (AF1)
+    GPIOA->MODER = (GPIOA->MODER & ~(GPIO_MODER_MODER9 | GPIO_MODER_MODER10))\
+                | (GPIO_MODER_MODER9_AF | GPIO_MODER_MODER10_AF);
+    GPIOA->AFR[1] = (GPIOA->AFR[1] & ~(GPIO_AFRH_AFRH1 | GPIO_AFRH_AFRH2)) |
+                1 << (1 * 4) | 1 << (2 * 4); // PA9, PA10
+    RCC->APB2ENR |= RCC_APB2ENR_USART1EN;
+#else
+#error "Wrong USARTNUM"
+#endif
+    // USARTX Tx DMA
+    USARTDMA->CPAR = (uint32_t) &USARTX->TDR; // periph
+    USARTDMA->CMAR = (uint32_t) tbuf; // mem
+    USARTDMA->CCR |= DMA_CCR_MINC | DMA_CCR_DIR | DMA_CCR_TCIE; // 8bit, mem++, mem->per, transcompl irq
+    // Tx CNDTR set @ each transmission due to data size
+    NVIC_SetPriority(DMAIRQn, 3);
+    NVIC_EnableIRQ(DMAIRQn);
+    NVIC_SetPriority(USARTIRQn, 0);
+    // setup usart1
+    USARTX->BRR = 480000 / 1152;
+    USARTX->CR3 = USART_CR3_DMAT; // enable DMA Tx
+    USARTX->CR1 = USART_CR1_TE | USART_CR1_RE | USART_CR1_UE; // 1start,8data,nstop; enable Rx,Tx,USART
+    while(!(USARTX->ISR & USART_ISR_TC)){if(--tmout == 0) break;} // polling idle frame Transmission
+    USARTX->ICR |= USART_ICR_TCCF; // clear TC flag
+    USARTX->CR1 |= USART_CR1_RXNEIE;
+    NVIC_EnableIRQ(USARTIRQn);
+}
+
+#if USARTNUM == 2
+void usart2_isr(){
+// USART1
+#elif USARTNUM == 1
+void usart1_isr(){
+#else
+#error "Wrong USARTNUM"
+#endif
+    #ifdef CHECK_TMOUT
+    static uint32_t tmout = 0;
+    #endif
+    if(USARTX->ISR & USART_ISR_RXNE){ // RX not emty - receive next char
+        #ifdef CHECK_TMOUT
+        if(tmout && Tms >= tmout){ // set overflow flag
+            bufovr = 1;
+            idatalen[rbufno] = 0;
+        }
+        tmout = Tms + TIMEOUT_MS;
+        if(!tmout) tmout = 1; // prevent 0
+        #endif
+        // read RDR clears flag
+        uint8_t rb = USARTX->RDR;
+        if(idatalen[rbufno] < UARTBUFSZI){ // put next char into buf
+            rbuf[rbufno][idatalen[rbufno]++] = rb;
+            if(rb == '\n'){ // got newline - line ready
+                linerdy = 1;
+                dlen = idatalen[rbufno];
+                recvdata = rbuf[rbufno];
+                // prepare other buffer
+                rbufno = !rbufno;
+                idatalen[rbufno] = 0;
+                #ifdef CHECK_TMOUT
+                // clear timeout at line end
+                tmout = 0;
+                #endif
+            }
+        }else{ // buffer overrun
+            bufovr = 1;
+            idatalen[rbufno] = 0;
+            #ifdef CHECK_TMOUT
+            tmout = 0;
+            #endif
+        }
+    }
+}
+
+// print 32bit unsigned int
+void printu(uint32_t val){
+    char bufa[11], bufb[10];
+    int l = 0, bpos = 0;
+    if(!val){
+        bufa[0] = '0';
+        l = 1;
+    }else{
+        while(val){
+            bufb[l++] = val % 10 + '0';
+            val /= 10;
+        }
+        int i;
+        bpos += l;
+        for(i = 0; i < l; ++i){
+            bufa[--bpos] = bufb[i];
+        }
+    }
+    bufa[l + bpos] = 0;
+    usart_send(bufa);
+}
+
+// print 32bit unsigned int as hex
+void printuhex(uint32_t val){
+    usart_send("0x");
+    uint8_t *ptr = (uint8_t*)&val + 3, start = 1;
+    int i, j;
+    for(i = 0; i < 4; ++i, --ptr){
+        if(!*ptr && start) continue;
+        for(j = 1; j > -1; --j){
+            start = 0;
+            register uint8_t half = (*ptr >> (4*j)) & 0x0f;
+            if(half < 10) usart_putchar(half + '0');
+            else usart_putchar(half - 10 + 'a');
+        }
+    }
+    if(start){
+        usart_putchar('0');
+        usart_putchar('0');
+    }
+}
+
+// dump memory buffer
+void hexdump(uint8_t *arr, uint16_t len){
+    for(uint16_t l = 0; l < len; ++l, ++arr){
+        for(int16_t j = 1; j > -1; --j){
+            register uint8_t half = (*arr >> (4*j)) & 0x0f;
+            if(half < 10) usart_putchar(half + '0');
+            else usart_putchar(half - 10 + 'a');
+        }
+        if(l % 16 == 15) usart_putchar('\n');
+        else if(l & 1) usart_putchar(' ');
+    }
+}
+
+#if USARTNUM == 2
+void dma1_channel4_5_isr(){
+    if(DMA1->ISR & DMA_ISR_TCIF4){ // Tx
+        DMA1->IFCR |= DMA_IFCR_CTCIF4; // clear TC flag
+        txrdy = 1;
+    }
+}
+// USART1
+#elif USARTNUM == 1
+void dma1_channel2_3_isr(){
+    if(DMA1->ISR & DMA_ISR_TCIF2){ // Tx
+        DMA1->IFCR |= DMA_IFCR_CTCIF2; // clear TC flag
+        txrdy = 1;
+    }
+}
+#else
+#error "Wrong USARTNUM"
+#endif