Acrel AIM-R100, Installation And Operation Manual

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equipment, but does not allow data exchange between independent terminal equipment, so that terminal
equipment will not occupy the communication line when they are initialized, but only respond to the query signal
arriving at the machine.
7.2 Introduction to function code
7.2.1 Function code 03H or 04H: register read
This function allows users to obtain data and system parameters collected and recorded by the device. There
is no limit to how much data a host can request at a time, but it cannot exceed the defined address range.
The following example reads a value from machine 01 at the address 0008H.
Master Send Data Slave Return Data
Address 01H Address 01H
Function 03H Function 03H
Start Address
High byte 00H Bytes 02H
Low byte 08H Data of
Registers
High byte 00H
number of
Registers
High byte 00H Low byte 50H
Low byte 01H
CRC code
High byte 21H
CRC code
High byte 74H Low byte 75H
Low byte 0CH
7.2.2 Function code 10H: write register
Function code 10H allows the user to change the contents of multiple registers. The time and date in the
meter can be written with this function number. The master can write up to 16 (32 bytes) of data at a time.
The following example is a device with a preset address of 01 date and time of 12:00 on Friday, December
01, 2009.From Monday to Sunday, 1 to 7 are used instead.
Master Send Data Slave Return Data
Address 01H Address 01H
Function 10H Function 10H
Start Address
High byte 00H
Start Address
High byte 00H
Low byte 04H Low byte 04H
number of
Registers
High byte 00H
number of
Registers
High byte 00H
Low byte 03H Low byte 03H
Bytes 06H
CRC code
High byte 31H
0004H data for
sending
High byte 09H Low byte C9H
Low byte 0CH
0005H data for
sending
High byte 01H
Low byte 05H