int main()
{
DDRB=0x01; // Set PB0 pin as output for display select
spi_masterInit(); // Initialize spi module
displayDriverInit(); // Initialize display chip
// clear display (all zero's)
for (char i =1; i<=2; i++)
{
spi_slaveSelect(0); // Select display chip
spi_write(i); // digit adress: (digit place)
spi_write(0); // digit value: 0
spi_slaveDeSelect(0); // Deselect display chip
}
wait(1000);
// write 4-digit data
for (char i =1; i<=2; i++)
{
spi_slaveSelect(0); // Select display chip
spi_write(i); // digit adress: (digit place)
spi_write(i); // digit value: i (= digit place)
spi_slaveDeSelect(0); // Deselect display chip
wait(1000);
}
wait(1000);
return (1);
}
// Set display off ('shut down')
void displayOff()
{
spi_slaveSelect(0); // Select display chip
spi_write(0x0C); // Register 0B: Shutdown register
spi_write(0x00); // -> 1 = Normal operation
spi_slaveDeSelect(0); // Deselect display chip
}
void spi_writeWord( unsigned char adress, unsigned char data )
{
spi_slaveSelect(0); // Select display chip
spi_write(adress); // write to adress
spi_write(data); // write data
spi_slaveDeSelect(0); // Deselect display chip
}
//Microcontrollers – TI2.3 - Opdrachten track 5 - versie 14-03-2016 Pagina 10 van 11
// Initialize the driver chip (type MAX 7219)
void displayDriverInit()
{
spi_slaveSelect(0); // Select display chip (MAX7219)
spi_write(0x09); // Register 09: Decode Mode
spi_write(0xFF); // -> 1's = BCD mode for all digits
spi_slaveDeSelect(0); // Deselect display chip
spi_slaveSelect(0); // Select dispaly chip
spi_write(0x0A); // Register 0A: Intensity
spi_write(0x04); // -> Level 4 (in range [1..F])
spi_slaveDeSelect(0); // Deselect display chip
spi_slaveSelect(0); // Select display chip
spi_write(0x0B); // Register 0B: Scan-limit
spi_write(0x01); // -> 1 = Display digits 0..1
spi_slaveDeSelect(0); // Deselect display chip
spi_slaveSelect(0); // Select display chip
spi_write(0x0C); // Register 0B: Shutdown register
spi_write(0x01); // -> 1 = Normal operation
spi_slaveDeSelect(0); // Deselect display chip
}
void spi_writeWord(unsigned char adress, unsigned char data) {
spi_slaveSelect(0); // Select display chip
spi_write(adress); // digit adress: (digit place)
spi_write(data); // digit value: i (= digit place)
spi_slaveDeSelect(0); // Deselect display chip
}