AccuEnergy AcuRev 1300, User Manual

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AcuRe
v
1300
intothe most signifcant bit (MSB) position. The LSB is extracted and examined, if the LSB
equals to 1, the register is exclusive ORed with a preset, fixed value; if the LSB equals to
0, noaction will be taken. This process is repeated until eight shifts have been performed.
Afterthe last (eighth) shift, the next 8-bit byte is exclusive ORed with the register’s current
value, and the process repeats for eight more shifts as described above. The final contents
of the register, after all the bytes of the message have been applied, is the CRC value.
Whenthe CRC is appended to the message, the low-order byte is appended first, followed
by the high-order byte.
5.2 Communication Format
This section is for instance will be as far as possible use as shown in table 5-3 format, (as hexadecimal
Numbers).Table 5-3 Protocol IIIustration
Addr: Slave device address
Fun: Function Code
Data start reg hi: Start register address, high byte
Data start reg lo: Start register address, low byte
Data #of reg hi: Number of registers, high byte
Data #of reg lo: Number of registers, low byte
CRC16 Hi: CRC high byte
CRC16 Lo: CRC low byte
1. Read Data (Function Code 03H)
Query:
Addr Fun
Data start
reg hi
Data start
reg lo
Data #of regs
hi
Data #of
regs lo
CRC16
Hi
CRC16
Lo
06H 03H 00H 00H 00H 21H 84H 65H