XC2200 Derivatives
System Units (Vol. 1 of 2)
Memory Organization
User’s Manual
3-32
V2.1, 2008-08
MemoryX2K, V1.3
Erase Security Page
Arguments: SECPA
Definition:
MOV XXAA
H
, XX80
H
MOV XX54
H
, XXA5
H
MOV SECPA, XX53
H
Timing: 3-cycle command that sets BUSY for the whole erasing duration.
Description: The addressed security page is erased.
This command is identical to the “
” command with the following exceptions:
The addressed page (SecP0 or SecP1) belongs not to the user visible flash memory
range. This command can only be executed after disabling of read protection and of
sector write protection.
See
“Protection Handling Examples” on Page 3-45
for a detailed description of re-
programming security pages.
The structure of the two security pages (SecP0 and SecP1) is described in
the Security Pages” on Page 3-43
After erasing a security page the new protection configuration (including keywords or
protection confirmation code) is valid directly after execution of this command.
While the IMB Core reads the protection configuration all DMU accesses to any flash
module are stalled.
This command must not be issued when the flash memory is in page mode. In this case
it is ignored and a sequence error is reported.
Disable Read Protection
Arguments: PWD
Definition:
MOV XX3C
H
, XXXX
H
MOV XX54
H
, PWD0
MOV XXAA
H
, PWD1
MOV XX54
H
, PWD2
MOV XXAA
H
, PWD3
MOV XX5A
H
, XX55
H
Timing: 6-cycle command that does not set any busy flag.
Description: Disable temporarily Flash read protection and — if activated — global write
protection of the whole flash memory. The RPA bit in IMB_IMBCTR is reset.
This is a protected command sequence, using four user defined passwords to release
this command or to check the programmed keywords. For every password one
command cycle is required. If the second or fourth password represents the code of the