Appendix 3 Buffer Memory - Mitsubishi Electric MELSEC iQ-R Series User Manual

Appendix 3
The buffer memory is the memory of C24 used for storing data (setting values, monitoring values, etc.) transmitted to or
received from the CPU module.
Initial values are set to the buffer memory.
When changing the initial values, set the parameters with Engineering tool.
For details, refer to the following section.
Page 422 PARAMETER SETTING
Configuration of buffer memory
A buffer memory consists of a user area and a system area as shown below.
■User area
• User area is an area where a user can read/write data.
• The user area consists of areas for storing setting values for data communication, for actual data communication, and for
storing communication status and communication error information.
• Read/write data from/to the user area in accordance with the instructions in the corresponding reference section.
■System area
System area is an area used by the C24 system.
Buffer memory assignment list
A buffer memory is configured with 16 bits per address.
Names, default values, etc. of each address of the buffer memory are as shown below.
Page 498 Buffer memory list
■Meaning of abbreviations in "Protocol" column
MC: MC protocol
Non: Nonprocedural protocol
Bi: Bidirectional protocol
Pd: Predefined protocol
■Meaning of symbols in "Protocol" column
The following symbols are assigned to protocols related to the setting values of a corresponding area and to areas used for
control by user settings.
RW: An area where data can be read/written to/from the CPU module and an target device.
R: An area where data can only be read from the CPU module and an target device.
: System area used by the system or area not used by the corresponding protocol.
APPENDICES APPENDIX
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Appendix 3 Buffer Memory

Buffer Memory