I was tinkering around with a sick Bally MPU board today (a rewired -17 monster for Grand Products 301), and was trying to figure out why the 6810 was not being selected...So I set the probe to DATA, and set a WRITE @ 0000 = 55, and then tried checking with the probe for results. Curiously enough, the probe showed nothing at all for A7 - Tri-state as far as it was concerned. I though maybe the 6800 pod was defective and pulled out another one, same result. A regular logic probe shows everything active. Now, I haven't experimented much with the probe sync, and this might be a flaw - or am I missing something obvious. I did only get four hours sleep last night due to some idiot breaking my shop window at 1AM and had to hang around till 4 for the glass folks...so - let's say I'm not at my sharpest today. Suggestions? John :-#)# How to subscribe or unsubscribe from TTL To do either you send email to "MajorDomo@flippers.com" and in the body you state either "Subscribe techtoolslist" or "Unsubscribe techtoolslist", note that the Subject is "" (Blank)... FTP site is: ftp://ftp.flippers.com/TTL/