2 LEDs used Bi-directionally

[Demon]

I'm building a matrix using this idea:
http://www.picbasic.co.uk/forum/showthread.php?t=14439



Pseudo-code:

GP0 TRIS 1     ' Input
GP1 TRIS 0     ' Output
GP1 = 1         ' Yellow ON

GP0 TRIS 0     ' Output
GP1 TRIS 1     ' Input
GP0 = 1         ' Red ON

Is that right?

And how do you turn them both off? Both output LOW?

Robert