2.6 Communications with a Mitsubishi PLC (A-compatible 1E Frame protocol)
Message Functions
2-136
Offsets (PARAM20 to PARAM27)
These parameters set the offset for the data address in the MP3000.
The MP3000 will offset the address by the number of words specified by the offset.
Note: An offset cannot be a negative value.
Offset parameters are provided for each of the target register types.
The following table lists the offset parameters.
The offset parameters that can be used depend on the function code.
The following table lists the valid parameters for each function code.
Data Relay Offset (PARAM28 and PARAM29)
This parameter is not used for the A-compatible 1E Frame protocol.
Data Register Offset (PARAM30 and PARAM31)
This parameter is not used for the A-compatible 1E Frame protocol.
Output Coil Offset (PARAM32 and PARAM33)
This parameter is not used for the A-compatible 1E Frame protocol.
Parameters
Meaning
Description
PARAM20 and
PARAM21
Coil Offset
Sets the offset to the word address for a coil.
PARAM22 and
PARAM23
Input Relay Offset
Sets the offset to the word address for an input relay.
PARAM24 and
PARAM25
Input Register Offset
Sets the offset to the word address for an input register.
PARAM26 and
PARAM27
Hold Register Offset
Sets the offset to the word address for a hold register.
Function Code
Function
Applicable Offset Parameters
01 hex
Reads the states of coils.
PARAM20 and PARAM21
02 hex
Reads the states of input relays.
PARAM22 and PARAM23
03 hex
Reads the contents of hold registers.
PARAM26 and PARAM27
04 hex
Reads the contents of input registers.
PARAM24 and PARAM25
05 hex
Changes the state of a single coil.
PARAM20 and PARAM21
06 hex
Writes to a single hold register.
PARAM26 and PARAM27
09 hex
Reads the contents of hold registers (extended).
PARAM26 and PARAM27
0A hex
Reads the contents of input registers (extended).
PARAM24 and PARAM25
0B hex
Writes to hold registers (extended).
PARAM26 and PARAM27
0D hex
Reads the contents of non-consecutive hold registers
(extended).
PARAM26 and PARAM27
0E hex
Writes to non-consecutive hold registers (extended).
PARAM26 and PARAM27
0F hex
Changes the states of multiple coils.
PARAM20 and PARAM21
10 hex
Writes to multiple hold registers.
PARAM26 and PARAM27
31 hex
Writes to the fixed buffer.
PARAM26 and PARAM27
32 hex
Reads from the random access buffer.
Cannot be received.
33 hex
Writes to the random access buffer.
PARAM26 and PARAM27