MC14489 7 segment display with multiple segments

[joekarl]

In the stampworks experiment book, there is an example (#31) showing how to hook up all 5 of the 7 segment displays on the PDB. I've duplicated the circuit using the MC14489 multiplexer. The code for this example is written in pbasic and I was wanting to write the code using java and the javelin stamp. Everything is coming together smoothly, however, the MC14489 requires a shiftOut to it of 24 bits. From what I've seen the java command for shiftOut can only send 16 bits. Is there a way to send 24 bits with the shiftOut command? Can I do it in too shiftOut commands? (each of 12 bits) Or if not, how can I duplicate this example using the javelin stamp.

[Peter Verkaik]

Yes, you can use multiple shiftOut(), for example 3x 8bits, or 2x 12bits, or 1x16 + 1x8
Just remember that if you use MSBFIRST, that you must leftshift the data
so the first bit to send is in bit position 15.

regards peter

[joekarl]

Okay, got it to work.

Here's my code:

    CPU.writePin(enablePin,true);
    CPU.delay(10);
    CPU.writePin(serialDataPin,true);
    CPU.writePin(clockPin,false);


    data1 = (int)displayControl;
    data1 = (data1 <<4) + (int)seg4;
    data2 = (int)seg3;
    data2 = (data2 <<4) + (int)seg2;
    data3 = (int)seg1;
    data3 = (data3 <<4) + (int)seg0;

    CPU.writePin(enablePin,false);
    CPU.shiftOut(serialDataPin, clockPin, 8, CPU.SHIFT_MSB, data1<<8);
    CPU.shiftOut(serialDataPin, clockPin, 8, CPU.SHIFT_MSB, data2<<8);
    CPU.shiftOut(serialDataPin, clockPin, 8, CPU.SHIFT_MSB, data3<<8);
    CPU.writePin(enablePin,true);

    CPU.delay(10);


    CPU.writePin(enablePin,false);
    CPU.shiftOut(serialDataPin, clockPin, 8, CPU.SHIFT_MSB, config<<8);
    CPU.writePin(enablePin,true);

Where seg0-seg4 are the segments on the display.
config is 8 bits that control which segments are on and whether they're using special hex codes.

Thanks for the help.

Karl