HD64F2149 Datasheet, PDF (165/1035 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

5.6.2 Instructions that Disable Interrupts
Instructions that disable interrupts are LDC, ANDC, ORC, and XORC. After any of these
instructions is executed, all interrupts except NMI are disabled and the next instruction is always
executed. When the I bit or UI bit is set by one of these instructions, the new value becomes valid
two states after execution of the instruction ends.
5.6.3 Interrupts during Execution of EEPMOV Instruction
Interrupt operation differs between the EEPMOV.B instruction and the EEPMOV.W instruction.
With the EEPMOV.B instruction, an interrupt request (including NMI) issued during the transfer
is not accepted until the move is completed.
With the EEPMOV.W instruction, if an interrupt request is issued during the transfer, interrupt
exception handling starts at a break in the transfer cycle. The PC value saved on the stack in this
case is the address of the next instruction.
Therefore, if an interrupt is generated during execution of an EEPMOV.W instruction, the
following coding should be used.
L1: EEPMOV.W
MOV.W R4,R4
BNE
L1
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