HD643303x Hitachi, HD643303x Datasheet - Page 115

• Manufacturer Part Number: HD643303x
• Description: Hitachi Microcomputer
• Manufacturer: Hitachi

5.5.2 Instructions that Inhibit Interrupts
The LDC, ANDC, ORC, and XORC instructions inhibit interrupts. When an interrupt occurs,
after determining the interrupt priority, the interrupt controller requests a CPU interrupt. If the
CPU is currently executing one of these interrupt-inhibiting instructions, however, when the
instruction is completed the CPU always continues by executing the next instruction.
5.5.3 Interrupts during EEPMOV Instruction Execution
The EEPMOV.B and EEPMOV.W instructions differ in their reaction to interrupt requests.
When the EEPMOV.B instruction is executing a transfer, no interrupts are accepted until the
transfer is completed, not even NMI.
When the EEPMOV.W instruction is executing a transfer, interrupt requests other than NMI are
not accepted until the transfer is completed. If NMI is requested, NMI exception handling starts at
a transfer cycle boundary. The PC value saved on the stack is the address of the next instruction.
Programs should be coded as follows to allow for NMI interrupts during EEPMOV.W execution:
L1: EEPMOV.W
MOV.W R4,R4
BNE
L1
100