|Re: NovRAM/NoV-32 experiences (MLDL2000 users: also for you)|
Message #12 Posted by Diego Diaz on 14 Feb 2008, 7:54 p.m.,
in response to message #11 by Meindert Kuipers
Sorry for being so late... I'm not at home and will still be out for three more weeks (in the Dominican Republic), with very little access to the i'net.
Certainly Clonix/NoV's also "sense" SYNC signal to begin bit-counting. But as far as I've able to test there is no relation between SYNC and those unwanted resets in the Clonix/NoV's code at start up, and also think that a some mA up or down (I've "abused" up to 100mA) won't affect the overall start up process.
I have a "suspictious" to be the culprit of such an undesirable behaviour attending to the following clues:
- I've never been able to reproduce "reset's" with "just" HEPAX loaded into NoVRAM into a clean [MEMORY RESET] HP-41.
- Most (all?) of the "reset" reports comes from systems using I/O Buffers (David Assm, CX Clock Alarms) and "heavy" usage of iterrupt area (H'XFF4...H'XFFA) AEC-ROM...
Clonix code is fairly simple (mostly the ClonixLP version) but NoV's are very tight coded so chances are that I/O buffer handling leads to situatios as those described by Meindert.
Also take into consideration that, though they share the same purpose, Clonix and MLDL2000 are completely different on their working principles: MLDL2000 is HW based (if you allow me to express it that way, Meindert) while Clonix is basically a SW "machine". So it looks "peculiar" that both approaches show that similarity in this "bug". My "conclusion" is that they both are "working as expected" and simply "pushing" HP-41 systems to their "real" limits (or even beyond that point).
In short there were very few chances to get such overloaded systems (CX with HEPAX + 2*X-MEM + AEC ROM + CCD [OS-X]...) in the late eighties...
Of course they *should* work properly with *any* legal configuration... but I'd like to test with a real HEPAX + real AEC + real CCD + 2*X-MEM (and some other "heavy" configs) to have a solid coparison base. (Any beta-tester volunteers?)
Anyhow, will keep on seeking to find out the way to avoid any unwanted behaviour on our beloved machines... and will need your help (as usual) to complete that task. Namely, any info regarding the I/O buffer handling will be sincerely welcome.
Best "Caribbean" wishes :-)