LAPIS Semiconductor ML610421, User Manual, Page: 79 / 437

ML610Q421/ML610Q422/ML610421 User’s Manual
Chapter 5 Interrupts (INTs)
5 – 10
5.2.9 Interrupt Request Register 0 (IRQ0)
Address: 0F018H
Access: R/W
Access size: 8 bits
Initial value: 00H
7 6 5 4 3 2 1 0
IRQ0
     
QNMI QWDT
R/W R/W R/W R/W R/W R/W R/W R/W R/W
Initial value 0 0 0 0 0 0 0 0
IRQ0 is a special function register (SFR) to request an interrupt for each interrupt source.
The watchdog timer interrupt (WDTINT) and the NMI interrupt (NMINT) are non-maskable interrupts that do not
depend on MIE. In this case, an interrupt is requested to the CPU regardless of the value of the Mask Interrupt Enable
flag (MIE).
Each IRQ0 request flag is set to “1” regardless of the MIE value when an interrupt is generated. By setting the IRQ0
request flag to “1” by software, an interrupt can be generated.
The corresponding flag of IRQ0 is set to “0” by hardware when the interrupt request is accepted by the CPU.
[Description of Bits]
•
QWDT (bit 0)
QWDT is the request flag for the watchdog timer interrupt (WDTINT).
QWDT Description
0 No request (initial value)
1 Request
•
QNMI (bit 1)
QNMI is the request flag for the NMI interrupt (NMINT).
QNMI Description
0 No request (initial value)
1 Request
Note:
When an interrupt is generated by the write instruction to the interrupt request register (IRQ0), the interrupt shift cycle
starts after the next 1 instruction is executed.