XC2200 Derivatives
System Units (Vol. 1 of 2)
Memory Organization
User’s Manual
3-30
V2.1, 2008-08
MemoryX2K, V1.3
The “
” command is only accepted if the addressed flash module is in
Page Mode (otherwise, a sequence error is reported instead of execution). With the
“
” command, the page mode is terminated, indicated by resetting the
related PAGE flag and the command mode is entered and the PROG flag in the status
register IMB_FSR is activated and the BUSY flag for the addressed module is set in
IMB_FSR. While BUSY is set the IMB Core does not accept any further commands.
When the program process has finished BUSY is cleared but PROG stays set. It
indicates which operation has finished and will be cleared by a System Reset or by
“
”.
Read accesses to the busy flash module are not possible. Reading a busy flash module
stalls until the flash module becomes ready again.
If write protection is installed for the sector to be programmed, the “
command is not accepted because the Flash is not in Page Mode (see description of the
“
” command).
If the page to be programmed is a security page (accepted only in security page mode),
the new protection configuration (including keywords or protection confirmation code) is
valid directly after execution of this command.
While the IMB Core reads the new protection configuration all DMU accesses to any
flash module are stalled.
Erase Sector
Arguments: SA
Definition:
MOV XXAA
H
, XX80
H
MOV XX54
H
, XXAA
H
MOV SA, XX33
H
Timing: 3-cycle command that sets BUSY for the whole erasing duration.
Description: The addressed physical sector in the flash array is erased. Following data
reads deliver all-zero data with correct ECC.
The erasing process is autonomously performed by the selected flash module. The CPU
is not occupied and can continue with its application.
The sector to be erased is addressed by SA (sector address) in the last command cycle.
With the last cycle of the “
” command, the command mode is entered,
indicated by activation of the ERASE flag and after start of erase operation also by the
related busy flag in the status register IMB_FSR. The BUSY flag is cleared after finishing
the operation but ERASE stays set. It can be cleared by a System Reset or the “
” command.