SSTV-Decoder/main.c

#include "adc.h"
#include "derivative.h"
#include "systick.h"
#include "tftlcd.h"
#include "uart.h"
#include <stdio.h>
#include <string.h>

#define ADC_M 2048

int main(void) {
    // Initialize
    uart_init(UART_MSG, 9600);  // Initialize UART1 with PC
    uart_rie_enable(UART_MSG);  // Enable UART1 receive interrupt
    LCD_Init();                 // Initialize LCD
    adc0_Init();                // Initialize ADC0

    uart_printf(UART_MSG, "System Clock: %lu\r\n", CORCLK);
    uart_printf(UART_MSG, "Bus Clock: %lu\r\n", BUSCLK);

    LCD_ShowString(LCD_W / 3, 0, "Audio Sample", 16, 0, 1);
    LCD_DrawLine(0, 16, LCD_W - 1, 16);

    uint16_t x0 = 16, y0 = 32;
    uint16_t x1 = LCD_W - 8, y1 = LCD_H - 16;
    uint16_t ym = (y0 + y1) / 2;
    LCD_DrawLine(x0, y0, x0, y1);
    LCD_DrawLine(x0, ym, x1, ym);
    LCD_ShowChar(0, y0, 'A', 16, 0);
    LCD_ShowChar(x1, ym, 'T', 16, 0);

    LCD_SetColor(BACK_COLOR);

    int16_t res;
    uint16_t pos[x1 - x0 - 1];
    uint16_t x = x0 + 1, y;
    uint32_t timer = 0;

    for (;;) {
        if (timer_expired_10us(&timer, 5)) {
            LCD_DrawPoint(x, pos[x - x0 - 1], BACK_COLOR);

            res = adc0_TR_DATA() - 1550;
            y = ym + res * (y1 - ym) / ADC_M;
            LCD_DrawPoint(x, y, RED);
            LCD_DrawPoint(x, ym, BLACK);

            pos[x - x0 - 1] = y;
            x = x + 1 < x1 ? x + 1 : x0 + 1;
        }
    }
}