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Siemens VDO Preliminary User’s Manual U17566EE1V2UM00
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VDO
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Chapter 9 ROM Correction Function (ROMC)
This microcontroller features following ROM correction facilities:
• “DBTRAP” ROM correction:
– 1x 8 channels for VFB flash memory and ROM
– 1 x 8 channels for VSB flash memory (for µPD70F3426 only)
The individual channels of each “DBTRAP” ROM correction are identified by
“m” (m = 0 to 7)
Caution
During self-programming make sure to disable all ROM correction facilities, as
enabled ROM corrections may conflict with the internal firmware.
9.1 Overview
The ROM Correction Function is used to replace part of the internal ROM or
flash memory with user defined data.
By using this function, program bugs found in the internal ROM and flash
memory can be corrected.
The “DBTRAP” ROM correction unit substitutes an instruction fetched from
ROM or flash memory by the DBTRAP instruction. Thus a DBTRAP exception
is excited and program execution branches to the DBTRAP vector
0000 0060
H
.
Note that the “DBTRAP” ROM correction unit is utilized by the N-Wire on-chip
debug unit. Therefore ROM corrections by DBTRAP are not available, when N-
Wire on-chip debugging is performed.
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