If you've got a MiniMem cartridge you can use EasyBug to 'switch the card on' and check you can read the DSR. There's details on a thread somewhere ...
Edit: Take a look at this post: http://atariage.com/...ug#entry3039394 If the first 2 bytes at >4000 aren't AA 00 then there's a problem reading the DSR. Assuming you've got a MiniMem cartridge to hand of course, and the CorComp card resides at CRU address >1100. You'd need to look at further bytes to completely confirm, but you'd need a dump of the EPROMs to compare against.
Yeh, I remember seeing that some time back, but the problem is as I turn on the system it locks. Now to be honest, I just realized that I am using a Corcomp Ramdisk at the same time, so I will take it out and try the rig. But the Ramdisk, or at least the 32k memory part of it works fine(tested with the Corcomp diagnostic cartridge), and the Call RAMGR function in its DSR is good, and I just formatted a MFM drive on the TI rig I am using with a HFDC installed, so I assume it's good. I was thinking maybe that either a PAL chip on Corcomp controller could be a problem or there are two chips, the MCM2114P SRAM and RCA CD4069UBE CMOS Hex inverter(don't know any thing about these chips), that I thought could be a problem. Or the 74LS123 chip(My tester does not have a listing for these and cannot identify it when it is plugged into the socket), but I haven't been able to search for a spare yet. Since I got my HFDC functional a couple of weeks ago, its priority has fallen. Still working on my cars till 9 or 10 at night, after work.
Edited by RickyDean, Fri Jan 15, 2016 11:40 AM.