Mitsubishi Q Mode, Programming Manual

Page: 98 / 126

9 - 6
MELSEC-Q/QnA
9. COMPLETE DERIVATIVE PID CONTROL INSTRUCTIONS AND
PROGRAM EXAMPLES
(4) Execute the PID57 instruction only after the PIDINIT and PIDCONT instructions
have been executed.
An error will occur if the PID57 instruction is executed before the PIDINIT and
PIDCONT instructions.
(5) Designate the loop number indicated by
S1
with a screen number from "1" to "4",
as shown below:
Screen Number Loop Numbers to be Monitored
1 Loop 1 to loop 8
2
Loop 9 to loop 16
3
Loop 17 to loop 24
4
Loop 25 to loop 32
(6) The initial screen display request, designated by
S2
, displays the characters in the
still portion of the monitor screen.
To make the initial screen display request, set "0" for
S2
.
Characters besides the bar graphs and numeric data will be not displayed unless
the initial screen display request is executed.
(7) After the initial screen is displayed, the value designated by
S1
is automatically
stored in
S2
and then the PID control monitor function is executed.
If the device designated by
S2
is a file register, do not set the memory protect
function for the file register ON.
If the memory protect function is ON, the screen cannot display the monitor data
correctly.
(8) The initial screen display request should only be executed once in response to
the first PID57 instruction after the start of QnACPU operation.
If it is executed every scan, the bar graphs and numeric data will not be
displayed, although the characters in the still portion are displayed.
(9) To monitor PID control status with the AD57(S1), a character generator ROM and
canvas ROM must be loaded to the AD57(S1).
The characters shown in Figure 9.1, corresponding to character codes 000 to
00B
H
, must be created in the character generator ROM.
If these characters are not created, bar graphs cannot be displayed.
Refer to the following manuals for details on creating the character generator
ROM and canvas ROM.
• SW1GP-AD57P Operating Manual