Found these inside a non-working 71B

[MikeSD]

(03-12-2018 12:09 PM)Paul Berger (Canada) Wrote:  For testing you don't need to cut anything as long as there is no HPIL module installed. Pin 9 (Dout) from #5 in your diagram by default goes to the HPIL port. The wire that you soldered into the via under the resistor taps into that connection, just connect it to 8 (Din) on the back RAM and leave 9 (Dout) on the front RAM unconnected. Taking another look at your diagram you could just remove the connection from 9 of the the front RAM and you should be OK as long as there is no HPIL module installed.

If you wish to make this permanent, or mount a module in the top left, where you found the math module.

The memory will show up as system RAM, when memory is converted to port RAM an identifying signature is written at the beginning of the memory in the module, and since RAM is volatile, when you power it on, the contents will be random.

Paul.

Something is still wrong then. I removed the wire add mem still says 15,391. Consistent but wrong. I'll buzz everything out again when I get home. I'm going to spend a little more time on this, then go remove the FORTH and see if the 71B is working without these.

Even sys RAM can be made independent with FREE and CLAIM. How is this RAM referenced?