Thread: hp-41cx / NoV-64d / Hepax XF multi-function

[kj.vandelooij]

Hi Diego,

Good to hear from you! I hope you are doing well.

I Switched to chip 1. An existing program

01 LBL TST
02 XF
03 0

with some string in alpha, does return the length of the string. Next, I erased to program and keyed it in again.

01 LBL TST
02 XF
03 0

Back stepping shows

01 LBL TST
02 XROM 07,53
03 0

Running the program yields 'nonexistent'. After a couple of times <- on, normal behavior is restored, and the program can be viewed as

01 LBL TST
02 XF
03 0

again, and it runs fine.

I got the same result for chip 2 and 3. So, yes the same problem occurs in all four cases, that is, with each of the four RAM chips.

Next, I cleared all four chips by
1) setting the control word
2) power cycle
3) "OK" 8 CLRAM
4) "OK" 9 CLRAM
5) "OK" 10 CLRAM
6) "OK" 11 CLRAM
7) powercycle
8) HEPROOM
9) HEPCHN?

In my case at least, the second power cycle was needed because without it, HEPROOM resulted in H:NO FILESYS. After the power cycle HEPROOM returned 2610 and HEPCHN? in 089AB0.

I am curious to the reason of why you suspect chip 0 might perhaps be faulty. Is there a more extensive way of testing it?

Greetings, and best wishes

Kees Jan

P.S. Congratulations on your latest product. If I need to continue running CLRAM as often as I did the last couple of days, I might need to consider a purchase :-)