HP-71 Diagnostics
|
06-06-2020, 04:07 PM
Post: #5
|
|||
|
|||
RE: HP-71 Diagnostics
Thanks Dave
I have contacted the seller as i left feedback, no response yet... Based on your suggestion I looked at the FRAM Chapter 9.. maybe there will be some inspiration, but it does look like the "Module" has to be in PORT 1... I was almost sure that it was the OD short on pin 11, which took care of that little detail. That pin is marked HALT in all other ports, including the IL one I have an "exploded" 71 for experiments (and to Control the World) which I could use to "cut" that OD track on the PCB for one of the ports and determine if: 1) the 71 will turn on at all - i honestly suspect it wont, there will likely not be any D-In to configure where the ROM would reside in the memory stack 2) if it does, then poke around (and share what I find here) In the BRILLIANT 71B Compendium from Sylvain there is a link to a ROM-dump made by J-F, so one is available. Playing with that will have to wait to next time it rains The journey continues (06-06-2020 01:28 PM)Dave Frederickson Wrote: One feature of the Diag ROM and Port 1 is that they be capable of disabling the system ROM. They do this by shorting the Output Disable signal, OD, to VDD. |
|||
« Next Oldest | Next Newest »
|
User(s) browsing this thread: 1 Guest(s)