restructuring

2026-02-28 11:54:30 +03:00 · 2022-03-10 11:04:14 +03:00
parent 29560b7c0c
commit 733dbd75d2
1758 changed files with 14 additions and 26855 deletions
--- a/deprecated/F0/uart/main.c
+++ b/deprecated/F0/uart/main.c
@@ -0,0 +1,114 @@
+/*
+ * main.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 "usart.h"
+
+static uint32_t stk_ctr = 0;
+
+/* Called when systick fires */
+void sys_tick_handler(void){
+    pin_toggle(GPIOB, GPIO3);
+    ++stk_ctr;
+}
+
+/*
+ * Set up timer to fire every x milliseconds
+ * This is a unusual usage of systick, be very careful with the 24bit range
+ * of the systick counter!  You can range from 1 to 2796ms with this.
+ */
+static void systick_setup(int xms){
+    static int curms = 0;
+    if(curms == xms) return;
+    // 6MHz
+    systick_set_clocksource(STK_CSR_CLKSOURCE_EXT);
+    /* clear counter so it starts right away */
+    STK_CVR = 0;
+
+    systick_set_reload(6000 * xms);
+    systick_counter_enable();
+    systick_interrupt_enable();
+    curms = xms;
+}
+
+/* set STM32 to clock by 48MHz from HSI oscillator */
+static void clock_setup(void){
+    rcc_clock_setup_in_hsi_out_48mhz();
+    //rcc_clock_setup_in_hse_8mhz_out_48mhz();
+
+    /* Enable clocks to the GPIO subsystems (A&B) */
+    RCC_AHBENR = RCC_AHBENR_GPIOAEN | RCC_AHBENR_GPIOBEN;
+}
+
+static void gpio_setup(void){
+    // Set green led (PB3) as output
+    gpio_mode_setup(GPIOB, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO3);
+}
+
+/**
+ * reverce line
+ */
+char *rline(char *in, int L){
+    static char out[UARTBUFSZ];
+    if(L > UARTBUFSZ - 1) return in;
+    char *optr = out, *iptr = &in[L-1];
+    for(; L > 0; --L) *optr++ = *iptr--;
+    *optr = '\n';
+    return out;
+}
+
+
+int main(void){
+    clock_setup();
+    gpio_setup();
+    usart2_setup();
+
+    systick_setup(500); // 1Hz in normal mode
+
+    const char dummy[] = "dummy text\n", err[] = "Error!\n";
+    char *txt;
+    int L = 0, dummyctr = 0;
+    uint32_t ostctr = 0;
+
+    while (1){
+        if(L){ // there's something to send
+            if(ALL_OK == usart2_send(txt, L)){
+                L = 0;
+            }else
+                usart2_send_blocking(err, sizeof(err));
+        }else if(ostctr != stk_ctr){
+            ostctr = stk_ctr;
+            if(++dummyctr > 10){ // once per 5 seconds
+                dummyctr = 0;
+                usart2_send(dummy, sizeof(dummy));
+            }
+        }
+        if(usart2rx()){ // data received
+            L = usart2_getline(&txt);
+            if(L){
+                txt = rline(txt, L);
+                ++L; // for trailing '\n'
+            }
+        }
+    }
+    return 0;
+}
+