new structure

src/main.c

@@ -43,21 +43,14 @@ int main()
 	sleep_ms(100);
 	tft_start_pixels(lcd_config.pio, lcd_config.sm);
 	while (true){
-		for(size_t i = 0; i < 8; i++) {
-			tft_fill(0);
-			dma_channel_wait_for_finish_blocking(dma_chan);
-		}
 		tft_start_pixels(lcd_config.pio, lcd_config.sm);
-		absolute_time_t start = get_absolute_time();
+		tft_fill(0);
-		for(size_t i = 0; i < 8; i++) {
+		dma_channel_wait_for_finish_blocking(dma_chan);
-			tft_fill(31807);
+		sleep_ms(1000);
-			dma_channel_wait_for_finish_blocking(dma_chan);
+		tft_start_pixels(lcd_config.pio, lcd_config.sm);
-		}
-		absolute_time_t end = get_absolute_time();
-		volatile int64_t diff = absolute_time_diff_us(start, end);
 		tft_fill(31807);
 		dma_channel_wait_for_finish_blocking(dma_chan);
-		// actual refresh rate ~25hz
+		sleep_ms(1000);
 	}
 	return 0;
 }

src/tft/tft.c

@@ -60,13 +60,17 @@ void tft_init(const struct tft_config* config, int dma_channel) {
     gpio_put(tft_cfg.gpio_bl, 1);
 }
 void tft_fill(uint16_t color) {
-    uint32_t color_left = ((uint32_t)color) << 16;
+    for(size_t i = 0; i < 8; i++) {
-    uint32_t two = 0;
+		dma_channel_wait_for_finish_blocking(dma_chan);
-    two |= color_left;
+        uint32_t color_left = ((uint32_t)color) << 16;
-    two |= color;
+        uint32_t two = 0;
-    uint32_t pix_buf[320*480/4]; 
+        two |= color_left;
-	for(size_t i = 0; i < 320*480/4; i++) {
+        two |= color;
-		pix_buf[i] = two;
+        uint32_t pix_buf[320*480/4]; 
+	    for(size_t i = 0; i < 320*480/4; i++) {
+	    	pix_buf[i] = two;
+	    }
+        dma_channel_set_read_addr(dma_chan, pix_buf, true);
 	}
-    dma_channel_set_read_addr(dma_chan, pix_buf, true);
+
 }