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CHAPTER 22 ROM CORRECTION
(2) Comparator
The comparator always compares the correction address values in correction address registers 0 and 1
(CORAD0 and CORAD1) with the fetch address value. If the correction address coincides with the fetch
address value when bit 1 (COREN0) or bit 3 (COREN1) of the correction control register (CORCN) is 1, the
ROM correction circuit generates a correction branch processing request signal (BR !F7FDH).
22.3 Registers Controlling ROM Correction
ROM correction is controlled by the correction control register (CORCN).
(1) Correction control register (CORCN)
This register controls generation of the correction branch processing request signal when the correction
address in correction address register 0 or 1 coincides with the fetch address. It consists of correction enable
flags (COREN0 and COREN1) that enable or disable detection of coincidence by the comparator and
correction status flags (CORST0 and CORST1) that indicate coincidence.
CORCN is set by using a 1-bit or 8-bit memory manipulation instruction.
This register is set to 00H when the RESET signal is input.