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41CL MMU Backup
05-30-2020, 05:22 AM (This post was last modified: 05-30-2020 06:17 AM by Ángel Martin.)
Post: #8
RE: 41CL MMU Backup
I hope I'm not confusing things, but If I understand the concept YFWR (1) temporarily remaps page #4 to 0x804, then (2) it runs the transient code, then (3) does the flash writing and then re-maps page #4 to its previous setting.

But this means than when using YFWR on 0x804 itself the information written to flash is under the conditions of step (2), so it says "page #4 is mapped to 0x804". Therefore restoring that block with YMCPY to 804 is going to preempt the actual page#4 mapping (in your case to the Library#4).

An interesting problem... maybe you can try to do a manual re-mapping to Library#4 after YFWR but you cannot perform any Library#4 dependent action until that is done, which it's unlikely unless the MMU is entirely disable of course.

"804>1F1"
YFWR - saves MMU settings with INCORRECT page#4

Then to restore things:

MMUDIS - disables MMU, so plain YFNZ is active
"1F1>804"
YMCPY - this step breaks the current Library#4 mapping
"804040-8120"
YPOKE - to restore that mapping
MMUEN - enables all mappings, so YFNX is active

I guess this means I should probably modify the YRALL routine in the PWRX module to include the fix, it was written with a previous version of YFWR (the one still included in YFNZ) that did not alter page#4 mapping in the saved flash block.
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Messages In This Thread
41CL MMU Backup - twoweims - 05-28-2020, 10:15 PM
RE: 41CL MMU Backup - Monte Dalrymple - 05-29-2020, 04:07 PM
RE: 41CL MMU Backup - twoweims - 05-29-2020, 04:44 PM
RE: 41CL MMU Backup - Monte Dalrymple - 05-29-2020, 05:49 PM
RE: 41CL MMU Backup - twoweims - 05-29-2020, 08:50 PM
RE: 41CL MMU Backup - Monte Dalrymple - 05-29-2020, 10:09 PM
RE: 41CL MMU Backup - twoweims - 05-30-2020, 01:05 AM
RE: 41CL MMU Backup - Ángel Martin - 05-30-2020 05:22 AM
RE: 41CL MMU Backup - twoweims - 05-30-2020, 02:32 PM
RE: 41CL MMU Backup - Ángel Martin - 05-30-2020, 03:45 PM
RE: 41CL MMU Backup - Ángel Martin - 05-31-2020, 06:09 AM
RE: 41CL MMU Backup - grsbanks - 05-30-2020, 08:27 AM
RE: 41CL MMU Backup - Ángel Martin - 05-30-2020, 03:52 PM
RE: 41CL MMU Backup - Monte Dalrymple - 05-30-2020, 06:47 PM
RE: 41CL MMU Backup - rprosperi - 05-30-2020, 10:36 PM
RE: 41CL MMU Backup - Monte Dalrymple - 05-30-2020, 11:58 PM
RE: 41CL MMU Backup - rprosperi - 05-31-2020, 03:00 AM
RE: 41CL MMU Backup - Monte Dalrymple - 08-07-2021, 02:07 AM
RE: 41CL MMU Backup - Ángel Martin - 05-31-2020, 06:55 AM
RE: 41CL MMU Backup - Monte Dalrymple - 05-31-2020, 06:22 PM
RE: 41CL MMU Backup - twoweims - 05-30-2020, 08:26 PM
RE: 41CL MMU Backup - Monte Dalrymple - 05-30-2020, 10:07 PM
RE: 41CL MMU Backup - twoweims - 05-31-2020, 06:30 PM
RE: 41CL MMU Backup - rprosperi - 05-31-2020, 06:51 PM
RE: 41CL MMU Backup - twoweims - 05-31-2020, 07:44 PM
RE: 41CL MMU Backup - rprosperi - 05-31-2020, 08:09 PM
RE: 41CL MMU Backup - twoweims - 06-01-2020, 09:24 PM
RE: 41CL MMU Backup - Monte Dalrymple - 06-01-2020, 10:48 PM
RE: 41CL MMU Backup - twoweims - 06-01-2020, 11:48 PM
RE: 41CL MMU Backup - Monte Dalrymple - 06-02-2020, 01:42 AM
RE: 41CL MMU Backup - grsbanks - 06-04-2020, 07:14 PM
RE: 41CL MMU Backup - Monte Dalrymple - 06-04-2020, 08:50 PM



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