This topic shows an other example of interfacing PIC18F4550 microcontroller with 1.8″ ST7735R SPI TFT display. ADC (Analog-to-Digital Converter) module is included in this example with 2 channels and the result is shown in the following video:
Related Topic:
Interfacing PIC18F4550 with 1.8″ TFT display
PIC18F4550 With ST7735 TFT and ADC example circuit:
Our example circuit schematic is shown below.
PIC18F4550 With ST7735 TFT and ADC example CCS C code:
For this project we need a driver for the ST7735 TFT display. This driver can be found in the post at:
ST7735 SPI TFT Display Driver for CCS PIC C compiler
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 | /* PIC18F4550 microcontroller with ST7735R SPI TFT and 2 ADC channels ST7735 TFT display driver for CCS PIC C compiler is required */ // TFT module connections #define TFT_CS PIN_D1 #define TFT_DC PIN_D0 #define TFT_SPI_HARDWARE // End TFT module connections #include <18F4550.h> #device ADC = 8 #fuses NOMCLR HSPLL PLL2 CPUDIV1 #use delay(clock = 48000000) #include <ST7735_TFT.c> #use fast_io(D) unsigned int8 i, j, k, pos_x0, pos_x, pos_y; void main(){ setup_adc_ports(AN0_TO_AN1); // Configure AN0 and AN1 as analog inputs setup_adc(ADC_CLOCK_DIV_64); // Set ADC conversion time to 64Tosc set_adc_channel(0); // Select channel AN0 TFT_BlackTab_Initialize(); fillScreen(ST7735_BLACK); pos_x0 = read_adc(); pos_y = 0; while(TRUE){ i = read_adc(); set_adc_channel(1); // Select channel AN1 pos_x = i / 2; if(pos_x0 <= pos_x) for(j = pos_x0; j < pos_x + 1; j++) drawPixel(j, pos_y, ST7735_YELLOW); else for(j = pos_x0; (j + 1) > pos_x; j--) drawPixel(j, pos_y, ST7735_YELLOW); pos_x0 = pos_x; k = read_adc(); set_adc_channel(0); // Select channel AN0 delay_ms(k); pos_y++; if(pos_y > _height){ fillScreen(ST7735_BLACK); pos_y = 0; } } } |
