AccuEnergy AcuRev 2000, User Manual

Page: 127 / 270

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2. Read the status of DI (Function Code 02)
Query
On top of slave device address and function code, query frame must contain the digital
input register starting address and the number of registers to be read. DI register address
starts from 0000H(DI1=0000H, DI2=0001H, DI3=0002H, DI4=0003H).
Table 5-6 depicts of reading DI1 to DI4 status of the slave device with the address of 17.
Addr Fun
DI start
addr hi
DI start
addr lo
DI num
hi
DI num
lo
CRC16
hi
CRC16
lo
11H 02H 00H 00H 00H 04H 7BH 59H
Table 5-6 Query frame of reading DI status
Response
The slave device anwsers the master device's query. The response frame contains slave
device address, function code, data quantity and CRC check.Each DI utilizes one bit(1 = ON
, 0 = OFF).Table 5-7 depicts the response frame.
Addr Fun Byte count Data0 CRC16 hi CRC16 lo
11H 02H 01H 03H E5H 49H
Data Bytes
0 0 0 0 DI4 DI3 DI2 DI1
0 0 0 0 0 0 1 1
MSB LSB
Table 5-7 Response frame of reading DI status