h8s-2649 Renesas Electronics Corporation., h8s-2649 Datasheet - Page 130

• Manufacturer Part Number: h8s-2649
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 5 Interrupt Controller
5.7.2
The instructions that disable interrupts are LDC, ANDC, ORC, and XORC. After any of these
instructions are executed, all interrupts including NMI are disabled and the next instruction is
always executed. When the I bit is set by one of these instructions, the new value becomes valid
two states after execution of the instruction ends.
5.7.3
There are times when interrupt acceptance is disabled by the interrupt controller.
The interrupt controller disables interrupt acceptance for a 3-state period after the CPU has
updated the mask level with an LDC, ANDC, ORC, or XORC instruction.
5.7.4
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 transfer 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.
Rev. 2.00 Dec. 05, 2005 Page 92 of 724
REJ09B0200-0200
L1:
Instructions that Disable Interrupts
When Interrupts Are Disabled
Interrupts during Execution of EEPMOV Instruction
EEPMOV.W
MOV.W
BNE
R4,R4
L1