Omron C200H-ASC11, Manual, Page: 94 / 301

85
Details of the Data Exchange Methods
Section 6-3
6-3-6 Data Exchange Method No. 6
After the CPU Unit has written to the ASCII Unit’s shared memory area, it
sends an interrupt to the ASCII Unit, and during the interrupt subroutine, the
ASCII Unit reads from the shared memory.
Note See 6-4-9 Sending Interrupts from CPU Unit to ASCII Unit: PC Interrupts for
details on PC interrupts.
1,2,3... 1. The CPU Unit writes to the ASCII Unit shared memory area (IOWR Area)
when the IOWR instruction (#00
@@
) is executed in the ladder diagram.
2. The CPU Unit sends an interrupt to the ASCII Unit when the IOWR instruc-
tion (#CC00) is executed in the ladder diagram.
3. Once the interrupt is received by the ASCII Unit, data is read in the ASCII
Unit via the PC EGET command.
The following example is for a C200HX/HG/HE PC.
Note 1. The following IOWR instruction would be used if the ASCII Unit was unit
number 0 and the interrupt number was 2.
2. The structure of the IOWR instruction for the CS1-series PCs is shown be-
low.
Inter-
rupt
Shared memory
(IOWR Area)
3. Read
CPU Unit ASCII Unit
1. Write
2.
3.
IOWR
#00 @@
IOWR
#CC00
a
# @ 001
ON PC a GOSUB
PC EGET
(See notes 1, 2)
IOWR
#CC00
#0002
#0001
0 001
Always 0001.
Unit No.
Control code
Interrupt number
IOWR (223)
#CC00
#0002
#00010000
0001 0000
Unit No.
Always 0001.
Interrupt number (BCD)