max7219_8x8led.c File Reference

#include "fw_hal.h"

Go to the source code of this file.

Macros
#define	MAX7219_CS   P17
#define	DECODE_MODE   0x09
#define	INTENSITY   0x0A
#define	SCAN_LIMIT   0x0B
#define	SHUT_DOWN   0x0C
#define	DISPLAY_TEST   0x0F

Functions
void	MAX7219_write (uint8_t addr, uint8_t dat)
void	MAX7219_init (void)
void	SPI_init (void)
void	main ()

Variables
const uint8_t	numbers []

Macro Definition Documentation

DECODE_MODE

#define DECODE_MODE   0x09

Definition at line 28 of file max7219_8x8led.c.

DISPLAY_TEST

#define DISPLAY_TEST   0x0F

Definition at line 32 of file max7219_8x8led.c.

INTENSITY

#define INTENSITY   0x0A

Definition at line 29 of file max7219_8x8led.c.

MAX7219_CS

#define MAX7219_CS   P17

Demo: MAX7219 8x8 LED Matrix Board: STC8H1K08

P1.3 -> DIN P1.5 -> SCLK P1.7 -> CS

Definition at line 26 of file max7219_8x8led.c.

SCAN_LIMIT

#define SCAN_LIMIT   0x0B

Definition at line 30 of file max7219_8x8led.c.

SHUT_DOWN

#define SHUT_DOWN   0x0C

Definition at line 31 of file max7219_8x8led.c.

Function Documentation

main()

void main

(

void

)

Definition at line 93 of file max7219_8x8led.c.

{
    uint8_t pos = 0, size = sizeof(numbers), i, j;
 
    SYS_SetClock();
    // Configure GPIO pins before SPI and device
    GPIO_P1_SetMode(GPIO_Pin_3, GPIO_Mode_InOut_QBD);
    GPIO_P1_SetMode(GPIO_Pin_5|GPIO_Pin_7, GPIO_Mode_Output_PP);
    // Configure SPI and device
    SPI_init();
    MAX7219_init();
 
    while(1)
    {
        for (i = 0; i < 8; i++)
        {
            j = (pos + i) % size;
            MAX7219_write(i + 1, numbers[j]);
        }
        pos = (pos + 1) % size;
        SYS_Delay(100);
    }
}

MAX7219_init()

void MAX7219_init

(

void

)

Definition at line 64 of file max7219_8x8led.c.

{
    MAX7219_write(SHUT_DOWN,    0x01);      // 0x00:shutdown, 0x01:normal
    MAX7219_write(DECODE_MODE,  0x00);      // Bypass code B decoder, no-decode operation
    MAX7219_write(SCAN_LIMIT,   0x07);      // Scan-limit, 0:1-digit, 1:2-digits, ... 7:8-digits
    MAX7219_write(INTENSITY,    0x01);      // 0x00:min, 0xFF:max
    MAX7219_write(DISPLAY_TEST, 0x00);      // 0x00:normal, 0x01:test mode
}

MAX7219_write()

void MAX7219_write	(	uint8_t	addr,
		uint8_t	dat
	)

Definition at line 56 of file max7219_8x8led.c.

{
    MAX7219_CS = 0;
    SPI_TxRx(addr);
    SPI_TxRx(dat);
    MAX7219_CS = 1;
}

SPI_init()

void SPI_init

(

void

)

Definition at line 73 of file max7219_8x8led.c.

{
    // MAX7219 can work with frequency up to 20MHz
    SPI_SetClockPrescaler(SPI_ClockPreScaler_4);
    // Clock idles low
    SPI_SetClockPolarity(HAL_State_OFF);
    // Data transfer is driven by lower SS pin
    SPI_SetClockPhase(SPI_ClockPhase_LeadingEdge);
    // MSB first
    SPI_SetDataOrder(SPI_DataOrder_MSB);
    // Define the output pins
    SPI_SetPort(SPI_AlterPort_P12P54_P13_P14_P15);
    // Ignore SS pin, use MSTR to swith between master/slave mode
    SPI_IgnoreSlaveSelect(HAL_State_ON);
    // Master mode
    SPI_SetMasterMode(HAL_State_ON);
    // Start SPI
    SPI_SetEnabled(HAL_State_ON);
}

Variable Documentation

numbers

const uint8_t numbers[]

Initial value:

={
0x00,0x00,0x7C,0xC6,0xC6,0xCE,0xD6,0xD6,  
0xE6,0xC6,0xC6,0x7C,0x00,0x00,0x00,0x00,
0x00,0x00,0x18,0x38,0x78,0x18,0x18,0x18,  
0x18,0x18,0x18,0x7E,0x00,0x00,0x00,0x00,  
0x00,0x00,0x7C,0xC6,0x06,0x0C,0x18,0x30,  
0x60,0xC0,0xC6,0xFE,0x00,0x00,0x00,0x00,  
0x00,0x00,0x7C,0xC6,0x06,0x06,0x3C,0x06,  
0x06,0x06,0xC6,0x7C,0x00,0x00,0x00,0x00,  
0x00,0x00,0x0C,0x1C,0x3C,0x6C,0xCC,0xFE,  
0x0C,0x0C,0x0C,0x1E,0x00,0x00,0x00,0x00,  
0x00,0x00,0xFE,0xC0,0xC0,0xC0,0xFC,0x0E,  
0x06,0x06,0xC6,0x7C,0x00,0x00,0x00,0x00,  
0x00,0x00,0x38,0x60,0xC0,0xC0,0xFC,0xC6,  
0xC6,0xC6,0xC6,0x7C,0x00,0x00,0x00,0x00,  
0x00,0x00,0xFE,0xC6,0x06,0x06,0x0C,0x18,  
0x30,0x30,0x30,0x30,0x00,0x00,0x00,0x00,  
0x00,0x00,0x7C,0xC6,0xC6,0xC6,0x7C,0xC6,  
0xC6,0xC6,0xC6,0x7C,0x00,0x00,0x00,0x00, 
0x00,0x00,0x7C,0xC6,0xC6,0xC6,0x7E,0x06,  
0x06,0x06,0x0C,0x78,0x00,0x00,0x00,0x00}

Definition at line 34 of file max7219_8x8led.c.