41: Clear main memory without wiping extended memory?

[Dave Britten]

I just ran into a situation where about 60 registers were "missing" on my 41CX, likely due to some kind of corrupt buffers or memory pointers. The only way to fix this was, of course, the nuclear option of On-Backspace, which also wipes extended memory. Is there any way to wipe main memory without touching extended memory? Or maybe just fix the memory pointers?

[PeterP]

Not close to a 41 to try this, but it depends if you have access to a CLONIX or other modul. A CLRBUFs, CLRKEYS, CLPS, and CLRGS should mostly do the trick (it deletes all buffers, key assignments, programs and registers).

If you dont have access to CLRBUF and CLRKEY (ie some of Angel's moduls or the CCD or HEPAX have these commands), but know your way around synthetic programming you can set the curtain in a way to have all main memory be registers and do a CLRGS or all main memory be program and do a CLPS (from the CX).

[Craig Bladow]

Possibly setting SIZE to 0 and then back to the old value given by SIZE?.

[Dave Britten]

(02-22-2021 05:44 PM)Craig Bladow Wrote:  Possibly setting SIZE to 0 and then back to the old value given by SIZE?.

Didn't help, I'm afraid. That was how I confirmed the missing registers, though.

I figure this would be a simple fix with ZenROM or any of the other exotic development modules, but I just have Advantage and a couple HP application modules for my 41CX. Maybe some synthetic tricks could do it. I'm trying to figure out how to get a byte grabber assigned to a key other than LN, since I use programs with A-E local labels quite a bit.

Anyway, this is more for future reference if I get myself into another jam. I have a card reader on the way, so it'll simplify reloading important programs after a reset, at least.

[Sylvain Cote]

(02-22-2021 03:26 PM)Dave Britten Wrote:  I just ran into a situation where about 60 registers were "missing" on my 41CX, likely due to some kind of corrupt buffers or memory pointers.
The only way to fix this was, of course, the nuclear option of On-Backspace, which also wipes extended memory.

CLKEYS clear all key assignment.
ALMCAT then R/S to pause catalog then [GOLD] [C] on each alarm to clear them.
Removing all modules with a power cycle should removed all buffers related to these modules.

(02-22-2021 05:44 PM)Craig Bladow Wrote:  Possibly setting SIZE to 0 and then back to the old value given by SIZE?.

If you have no programs, no buffers, SIZE 000, you should get 319 registers in program mode.

(02-22-2021 03:26 PM)Dave Britten Wrote:  Or maybe just fix the memory pointers?

That can be done but you have to seriously know your way around.

(02-22-2021 03:26 PM)Dave Britten Wrote:  Is there any way to wipe main memory without touching extended memory?

Nop! without doing the above pointers manipulation.

[Dave Britten]

(02-22-2021 06:42 PM)Sylvain Cote Wrote:  

(02-22-2021 03:26 PM)Dave Britten Wrote:  I just ran into a situation where about 60 registers were "missing" on my 41CX, likely due to some kind of corrupt buffers or memory pointers.
The only way to fix this was, of course, the nuclear option of On-Backspace, which also wipes extended memory.

CLKEYS clear all key assignment.
ALMCAT then R/S to pause catalog then [GOLD] [C] on each alarm to clear them.
Removing all modules with a power cycle should removed all buffers related to these modules.

Good tips, thanks. I'll try those steps if I get myself in trouble again.

(02-22-2021 06:42 PM)Sylvain Cote Wrote:  

(02-22-2021 03:26 PM)Dave Britten Wrote:  Or maybe just fix the memory pointers?

That can be done but you have to seriously know your way around.

I definitely don't.