RL02 fault (OS/8)

I was trying to talk myself out of that one, but I suspect you're right :^P The problem I was thinking hopefully of was a checksum error caused by an aborted or other improper write... but then again the controller card and disk internal logic board probably do restrict writing by complete sectors? I'll have to download a copy of the RL02 manual from bitsavers to read while I'm sunning on my mom's terrace. Remember also that I had that problem occur once before (on my first boot and before the chip failed) but after powering everything down, removing and reinstalling the pack, powering up and rebooting (shades of Micro$hit!) it did boot to the OS/8 "." prompt and was functional at least to the point of displaying a directory... Anyway it'll be easy enough to write a simple program to display the error word on the Programmer's Panel display and backtrack from there... maybe it's a bad pack. Or a bad cable (I spent hours when I first got this drive trying to figure out why the fault light wouldn't go out, and tracked it down to a faulty clock signal from the controller card. More specifically there was a single hair-fine wire strand sticking out the bottom of my IDC connector where it plugged into the controller card and it was touching a passing trace. The original BERG conn. would not have had a clearance problem (to the butt end of cut cable) there. Although the pack (that I copied my SIMH OS/8 image onto) had no bad blocks on it that I could discern under RT-11, I wonder if there could have been some that make a difference to OS/8. I'm getting out of my depth here. Anyhow when I get home, I'll find out exactly what the error is (I never liked that idiot light precisely because it doesn' t tell you WHAT the fault IS!) -Charles