Mitsubishi MELSEC Q Series Reference Manual page 503

b15 b14 b13 b12 b11 b10
0 1/0 0 0 1/0
APPX - 7
4) Device qualification and indirect designation
(Device qualification: for [Designation-4])
This data item is for designating an arbitrary device number of the
same device by using the designation value in head device (or device)
as the offset value for the device number, and further adding the value
in the index register.
(Indirect designation: for [Designation-5])
By this data designation, the value stored in the designated head
device (or device) and the value stored in the immediately following
device memory define the address of the device memory to be
accessed by an external device.
Indirect designation can be used when accessing word devices.
a) Data communication in ASCII code
Designate only the device qualification data and send the following
value sequentially beginning from the most significant digit.
Designation value
"000"
"Z "
b) Data communication in binary code
Designate device qualification and indirect designation data, use
the following value and send it beginning from low byte (L: bits 0
to 7).)
b8 b7
0 0 0
c) The index registers (Z0 to Z15) can be used for extension setting
qualification.
Description
(Without device qualification)
Index register for device qualification
b0
Index register number designation (for device qualification)
"00 " without device qualification.
H
Indirect designation
0: Without indirect designation
1: With indirect designation
Device qualification designation
00: Without device qualification designation
01: With device qualification designation
APPENDICES
Remarks
–
Designate index register number by
converting it to 2-digit ASCII code
(decimal) and inserting it in the
field.
APPX - 7