Sending Interrupts - Omron C200H-ASC11 Manual

Overview of Data Exchanges
6-1-2

Sending Interrupts

72
5. The ASCII Unit sets an IOWR Request Flag for the CPU Unit. When an
IOWR (#FD00) instruction is executed, the CPU Unit writes data. Alter-
nately, the ASCII Unit sets an IORD Request Flag for the CPU Unit. When
an IORD (#FD00) instruction is executed, the CPU Unit reads data (sup-
ported only by the C200HX/HG/HE and CS1-series PCs).
IOWR (#FD00)
IORD (#FD00)
There are two methods for sending interrupts from the CPU Unit to the ASCII
Unit. It is not possible to send interrupts to the CPU Unit from the ASCII Unit.
1,2,3... 1. Interrupts are sent during the I/O refresh period. An interrupt number is set
in the allocated IR/CIO area word, and when the PC Interrupt Bit goes ON,
the ON PC command branches to the specified line number.
CPU Unit
Allocated words
Note PC interrupts are disabled while the ASCII Busy Flag is ON.
CPU Unit
Memory area setting
IOWR/IORD
Request Flag
I/O Memory
Interrupt during
I/O refresh
PC QREAD@
PC QWRITE@
Allocated words
I/O refresh
Read/write
ASCII Unit
ON PC (interrupt number)
GOSUB (line number)
Interrupt subroutine
Section 6-1
ASCII Unit
Variable