spimatrixledGo_main2.go

    // Initialize SPI on the SPI0 associated GPIO pins
    if err := rpio.SpiBegin(rpio.Spi0); err != nil {
        fmt.Println(err)
        os.Exit(1)
    }

    csPin.Output()
    rpio.SpiChipSelect(uint8(csPin)) // Select CE0 (csPin) as slave
    initMax7219()

    for {
        select {
        case <-stop:
            break
        default:
            for i := 0; i < NUM_CHARS; i++ {
                for j := 1; j < MATRIX_ROW+1; j++ {
                    // 'j' starts at 1 since it's also used to reference the MAX7219 display registers
                    // which start at offset 1.
                    writeMax7219(byte(j), disp1[i][j-1])
                }
                time.Sleep(500 * time.Millisecond)
            }
            break
        }
    }
    // Reset the SPI0 pins back to INPUT mode
    rpio.SpiEnd(rpio.Spi0)
    // Release SPI resources (e.g., mapped memory)
    rpio.Close()
}