Device Memory Read And Write; Considerations - Mitsubishi Electric MELSEC IQ-R series Reference Manual

17.4

Device Memory Read and Write

This section explains the specification content and examples of the control procedure when reading from/writing to the device
memory are as shown below.
For the message formats other than request data and response data, refer to the following sections.
Page 344 Message Format, Page 346 Details of Setting Data
To read and write the extended file register, use the commands dedicated to the extended file register.
Page 371 Read and Write Extended File Register

Considerations

The considerations when reading/writing device memory using the commands described in this section.
Considerations when accessing devices other than ACPU module
■Accessible devices
Only the devices with the same names that exist in ACPU can be accessed within the device range of AnACPU.
Page 352 Accessible device range
The following devices cannot be accessed from the external devices:
• Added devices
• Latch relay (L) and step relay (S)
• File register (R) of QnACPU
*1 Even when the latch relay (L) or step relay (S) is specified, the internal relay (M) can be accessed.
■Special relays and special registers
Special relays and special registers can be accessed within the following range.
• Access SM1000 to SM1255 by specifying M9000 to M9255.
• Access SD1000 to SD1255 by specifying D9000 to D9255.
■Universal model QCPU
Use the Universal model QCPU with a serial number whose first five digits are '10102' or later.
As for the serial number whose first five digits are '10101' or earlier, access using 2C/3C/4C frame.
17 COMMUNICATING USING 1C FRAMES
350
17.4 Device Memory Read and Write
*1