Service module (SM1C) and peripherial flags

[ThomasF]

(05-27-2024 10:43 AM)brouhaha Wrote:  I brought this up once before here, and people didn't seem to believe me.
...
but I don't recall anything in the service manual suggested to me that it had to be a double mem.

I can only agree - the DATA line must be fed to FI for the test to work (e.g. by connecting DATA and FI pins), and as my test and examine of the source code for the Service ROM shows, there must only by exactly 3 memory modules in the calculator when executing the test - otherwise it will fail.

It is also true that the Sevice Module SM-1C and the "IO PORT TEST" only works in a HP-41C (with 2 memory modules and the ET-11967 module) and can not be executed successfully in a CV or CX.
It must for the CV or CX be executed with another version of the Service Module (which support full memory) and a FI-wired module without any memory.

Cheers,
Thomas