From ae54b81f1ca0f271186a9a6d56677beea4230716 Mon Sep 17 00:00:00 2001
From: Marco Oliverio <marco@wolfssl.com>
Date: Sun, 4 Sep 2022 08:56:15 +0200
Subject: [PATCH] sensors: gps data

---
 src/main.c | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)

diff --git a/src/main.c b/src/main.c
index 6215a6d..4130dc9 100644
--- a/src/main.c
+++ b/src/main.c
@@ -2,6 +2,7 @@
 #include "fatfs/tf_card.h"
 #include <string.h>
 #include "gd32vf103_i2c.h"
+#include "minmea.h"
 
 //#define HZ2MS(X) ((uint64_t)((X * 53000.0)/(SystemCoreClock)))
 
@@ -33,6 +34,32 @@ void init_uart0(void)
     usart_interrupt_enable(USART0, USART_INT_RBNE);
 }
 
+void init_uart1(void)
+{
+	/* enable GPIO clock */
+    rcu_periph_clock_enable(RCU_GPIOA);
+    /* enable USART clock */
+    rcu_periph_clock_enable(RCU_USART1);
+
+    /* connect port to USARTx_Tx */
+    /* gpio_init(GPIOA, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_9); */
+    /* connect port to USARTx_Rx */
+    gpio_init(GPIOA, GPIO_MODE_IN_FLOATING, GPIO_OSPEED_50MHZ, GPIO_PIN_3);
+
+	/* USART configure */
+    usart_deinit(USART1);
+    usart_baudrate_set(USART1, 9600);
+    usart_word_length_set(USART1, USART_WL_8BIT);
+    usart_stop_bit_set(USART1, USART_STB_1BIT);
+    usart_parity_config(USART1, USART_PM_NONE);
+    usart_hardware_flow_rts_config(USART1, USART_RTS_DISABLE);
+    usart_hardware_flow_cts_config(USART1, USART_CTS_DISABLE);
+    usart_receive_config(USART1, USART_RECEIVE_ENABLE);
+    usart_transmit_config(USART1, USART_TRANSMIT_DISABLE);
+    usart_enable(USART1);
+
+    usart_interrupt_enable(USART1, USART_INT_RBNE);
+}
 
 #define MAX_ROW 20
 #define MAX_NMEA 192
@@ -297,6 +324,51 @@ static uint32_t bmp180_read_P(void)
     return (uint32_t)((data_xlsb + (data_lsb << 8) + (data_msb << 16)) >> (8 - BMP180_OSS));
 }
 
+static char uart_data_receive_blocking(uint32_t usart_periph)
+{
+    while (usart_flag_get(usart_periph, USART_FLAG_RBNE) != SET) {
+            continue;
+    }
+
+    return usart_data_receive(usart_periph);
+}
+
+static void get_nmea_line(char *buf)
+{
+    int i = 0;
+
+    while (uart_data_receive_blocking(USART1) != '$') {
+        /* sync with the beginning of the line */
+    }
+    buf[i++] = '$';
+    while(true) {
+        buf[i] = uart_data_receive_blocking(USART1);
+        if (buf[i] == '\n' || i >= MAX_NMEA)
+            break;
+        i++;
+    }
+    buf[i] = 0;
+}
+
+static int read_gps(struct minmea_sentence_gga *frame)
+{
+    char nmea_buf[MAX_NMEA];
+    int ret;
+
+    do {
+        get_nmea_line(nmea_buf);
+    } while(strncmp(nmea_buf, "$GPGGA", strlen("$GPGGA")) != 0);
+
+    ret = minmea_parse_gga(frame, nmea_buf);
+    if (!ret) {
+        LCD_ShowString(0, 0, (u8 *)("PARSING ERROR"), RED);
+        LCD_ShowString(0, 32, (u8 *)nmea_buf, RED);
+        delay_1ms(2000);
+    }
+
+    return 0;
+}
+
 int main(void)
 {
     uint8_t mount_is_ok = 1; /* 0: mount successful ; 1: mount failed */
@@ -310,6 +382,7 @@ int main(void)
     uint32_t up;
     uint32_t pressure;
     int32_t temperature;
+    struct minmea_sentence_gga gps_data = { 0 };
 
     SystemInit();
     /* Init GPIOs */
@@ -326,6 +399,7 @@ int main(void)
 
     /* HW init: uart, ADC, Display */
     init_uart0();
+    init_uart1();
     Lcd_Init();
 
     /* I2C init */
@@ -339,6 +413,14 @@ int main(void)
 
     while (1)
     {
+        read_gps(&gps_data);
+        LCD_Clear(BLACK);
+        snprintf(gps, MAX_ROW-1, "%d:%d:%d", gps_data.time.hours, gps_data.time.minutes, gps_data.time.seconds);
+        LCD_ShowString (0, 0, (u8 *)gps, GREEN);
+        snprintf(gps, MAX_ROW-1, "%d,%d", gps_data.latitude.value, gps_data.longitude.value);
+        LCD_ShowString (0, 16, (u8 *)gps, GREEN);
+        snprintf(gps, MAX_ROW-1, "H:%d", gps_data.altitude.value/gps_data.altitude.scale);
+        LCD_ShowString (0, 32, (u8 *)gps, GREEN);
         ut = bmp180_read_T();
         up = bmp180_read_P();