Posted by Andy Warne on 26, 2001 at 3:24 PM:
In Reply to: How old is your I-Pac? more posted by Mr Arcade on 26, 2001 at 11:56 AM:
The issue with older units was a batch of Cherry microswitches which are used on Happ joysticks which had a VERY bouncy contact on "break" (strange but true! the logic analyzer traces from these switches look like the Manhattan skyline! All switches bounce on "make" but not so much on break normally). I had to put a fix in to allow for these switches but that was many months ago.
This sounds like a stuck key and if the pass-thru keyboard stops it's worth trying another keyboard. Sometimes the voltage drop from the PC, via the I-PAC and onto the pass-thru keyboard gets too low for a small number of keyboards which are more sensitive to this. This is especially true when the PC power supply is running a bit on the low side on +5V.
: I have built several machines using the I-Pac. On 2 occasions I had glitches. I contacted Andy and he made it right both times. I can't remember how the first problem was solved...but on the second occasion he mailed an updated chip and it solved the problem.
: My only advice other than contacting Andy is to check your grounds.
: Mr Arcade