> -----Original Message-----
> For input, there are only 2 signals, BUSY and BUSY_N. Each of these can
> be read independenty.
As I recall, the way it worked was that the five switches (directional switches
and fire) were wired to the first five output bits, and the common return from
all five switches was wired to BUSY. To poll the joystick you'd cycle through
outputting ASCII 1, 2, 4, 8, and 16, and read BUSY each time. Whichever bits
resulted in assertion of BUSY meant that switch was currently closed.
jim
