![](/media/cache/img/default_profile.jpg.50x50_q85.jpg)
Programme de démo pour la gestion de 4 afficheurs 64 leds
main.cpp@1:61f61158c345, 2022-03-28 (annotated)
- Committer:
- vermaelen
- Date:
- Mon Mar 28 10:11:31 2022 +0000
- Revision:
- 1:61f61158c345
- Parent:
- 0:bd34a367f642
- Child:
- 2:675b923da5d2
v1;
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
icserny | 0:bd34a367f642 | 1 | /* 06_spi_max7219_led8x8 |
icserny | 0:bd34a367f642 | 2 | * |
icserny | 0:bd34a367f642 | 3 | * Simple demo to drive a 8x8-as LED matrix by a MAX7219 LED driver IC |
icserny | 0:bd34a367f642 | 4 | * After initialisation two characters (H and W) are displayed alternatively. |
icserny | 0:bd34a367f642 | 5 | * The MAX7219 IC is driven by hardware SPI: SPI0 module at PTD1, PTD2, PTD3. |
icserny | 0:bd34a367f642 | 6 | */ |
icserny | 0:bd34a367f642 | 7 | |
icserny | 0:bd34a367f642 | 8 | #include "mbed.h" |
vermaelen | 1:61f61158c345 | 9 | #include "lib_matrix.h" |
icserny | 0:bd34a367f642 | 10 | |
vermaelen | 1:61f61158c345 | 11 | SPI spi(D11,D12,D13); // Arduino compatible MOSI, MISO, SCLK |
vermaelen | 1:61f61158c345 | 12 | DigitalOut cs(D14); // Chip select |
vermaelen | 1:61f61158c345 | 13 | |
vermaelen | 1:61f61158c345 | 14 | int main() |
vermaelen | 1:61f61158c345 | 15 | { |
vermaelen | 1:61f61158c345 | 16 | cs = 1; // CS initially High |
vermaelen | 1:61f61158c345 | 17 | spi.format(8,0); // 8-bit format, mode 0,0 |
vermaelen | 1:61f61158c345 | 18 | spi.frequency(1000000); // SCLK = 1 MHz |
vermaelen | 1:61f61158c345 | 19 | Init_MAX7219(); // Initialize the LED controller |
vermaelen | 1:61f61158c345 | 20 | char tab[20]="HELLOWO&&&"; |
vermaelen | 1:61f61158c345 | 21 | int i=0; |
vermaelen | 1:61f61158c345 | 22 | while (1) { |
vermaelen | 1:61f61158c345 | 23 | disp(tab[i]); |
vermaelen | 1:61f61158c345 | 24 | i=(i+1)%10; |
vermaelen | 1:61f61158c345 | 25 | wait(0.5); |
vermaelen | 1:61f61158c345 | 26 | disp(' '); |
vermaelen | 1:61f61158c345 | 27 | wait(0.1); // 1 sec delay |
vermaelen | 1:61f61158c345 | 28 | |
vermaelen | 1:61f61158c345 | 29 | } |
vermaelen | 1:61f61158c345 | 30 | } |
icserny | 0:bd34a367f642 | 31 | |
vermaelen | 1:61f61158c345 | 32 | void disp(char c) |
vermaelen | 1:61f61158c345 | 33 | { |
vermaelen | 1:61f61158c345 | 34 | switch(c) { |
vermaelen | 1:61f61158c345 | 35 | case 'E' : |
vermaelen | 1:61f61158c345 | 36 | for(int i=1; i<9; i++) // Write first character (8 rows) |
vermaelen | 1:61f61158c345 | 37 | SPI_Write2(i,led_E[i-1]); |
vermaelen | 1:61f61158c345 | 38 | break; |
vermaelen | 1:61f61158c345 | 39 | case 'H' : |
vermaelen | 1:61f61158c345 | 40 | for(int i=1; i<9; i++) // Write first character (8 rows) |
vermaelen | 1:61f61158c345 | 41 | SPI_Write2(i,led_H[i-1]); |
vermaelen | 1:61f61158c345 | 42 | break; |
vermaelen | 1:61f61158c345 | 43 | case 'L' : |
vermaelen | 1:61f61158c345 | 44 | for(int i=1; i<9; i++) // Write first character (8 rows) |
vermaelen | 1:61f61158c345 | 45 | SPI_Write2(i,led_L[i-1]); |
vermaelen | 1:61f61158c345 | 46 | break; |
vermaelen | 1:61f61158c345 | 47 | case 'O' : |
vermaelen | 1:61f61158c345 | 48 | for(int i=1; i<9; i++) // Write first character (8 rows) |
vermaelen | 1:61f61158c345 | 49 | SPI_Write2(i,led_O[i-1]); |
vermaelen | 1:61f61158c345 | 50 | break; |
vermaelen | 1:61f61158c345 | 51 | case 'W' : // 1 sec delay |
vermaelen | 1:61f61158c345 | 52 | for(int i=1; i<9; i++) // Write second character |
vermaelen | 1:61f61158c345 | 53 | SPI_Write2(i,led_W[i-1]); |
vermaelen | 1:61f61158c345 | 54 | break; |
vermaelen | 1:61f61158c345 | 55 | case ' ' : // 1 sec delay |
vermaelen | 1:61f61158c345 | 56 | for(int i=1; i<9; i++) // Write second character |
vermaelen | 1:61f61158c345 | 57 | SPI_Write2(i,led_blank[i-1]); |
vermaelen | 1:61f61158c345 | 58 | break; |
vermaelen | 1:61f61158c345 | 59 | case '&' : // 1 sec delay |
vermaelen | 1:61f61158c345 | 60 | for(int i=1; i<9; i++) // Write second character |
vermaelen | 1:61f61158c345 | 61 | SPI_Write2(i,led_heart[i-1]); |
vermaelen | 1:61f61158c345 | 62 | break; |
vermaelen | 1:61f61158c345 | 63 | } |
vermaelen | 1:61f61158c345 | 64 | } |
icserny | 0:bd34a367f642 | 65 | /// Send two bytes to SPI bus |
icserny | 0:bd34a367f642 | 66 | void SPI_Write2(unsigned char MSB, unsigned char LSB) |
icserny | 0:bd34a367f642 | 67 | { |
icserny | 0:bd34a367f642 | 68 | cs = 0; // Set CS Low |
icserny | 0:bd34a367f642 | 69 | spi.write(MSB); // Send two bytes |
icserny | 0:bd34a367f642 | 70 | spi.write(LSB); |
icserny | 0:bd34a367f642 | 71 | cs = 1; // Set CS High |
icserny | 0:bd34a367f642 | 72 | } |
icserny | 0:bd34a367f642 | 73 | |
icserny | 0:bd34a367f642 | 74 | /// MAX7219 initialisation |
icserny | 0:bd34a367f642 | 75 | void Init_MAX7219(void) |
icserny | 0:bd34a367f642 | 76 | { |
icserny | 0:bd34a367f642 | 77 | SPI_Write2(0x09, 0x00); // Decoding off |
icserny | 0:bd34a367f642 | 78 | SPI_Write2(0x0A, 0x08); // Brightness to intermediate |
icserny | 0:bd34a367f642 | 79 | SPI_Write2(0x0B, 0x07); // Scan limit = 7 |
icserny | 0:bd34a367f642 | 80 | SPI_Write2(0x0C, 0x01); // Normal operation mode |
icserny | 0:bd34a367f642 | 81 | SPI_Write2(0x0F, 0x0F); // Enable display test |
icserny | 0:bd34a367f642 | 82 | wait_ms(500); // 500 ms delay |
icserny | 0:bd34a367f642 | 83 | SPI_Write2(0x01, 0x00); // Clear row 0. |
icserny | 0:bd34a367f642 | 84 | SPI_Write2(0x02, 0x00); // Clear row 1. |
icserny | 0:bd34a367f642 | 85 | SPI_Write2(0x03, 0x00); // Clear row 2. |
icserny | 0:bd34a367f642 | 86 | SPI_Write2(0x04, 0x00); // Clear row 3. |
icserny | 0:bd34a367f642 | 87 | SPI_Write2(0x05, 0x00); // Clear row 4. |
icserny | 0:bd34a367f642 | 88 | SPI_Write2(0x06, 0x00); // Clear row 5. |
icserny | 0:bd34a367f642 | 89 | SPI_Write2(0x07, 0x00); // Clear row 6. |
icserny | 0:bd34a367f642 | 90 | SPI_Write2(0x08, 0x00); // Clear row 7. |
icserny | 0:bd34a367f642 | 91 | SPI_Write2(0x0F, 0x00); // Disable display test |
icserny | 0:bd34a367f642 | 92 | wait_ms(500); // 500 ms delay |
icserny | 0:bd34a367f642 | 93 | } |