Holip HLP-A Series, Instruction Manual

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HLP-A Series
HLP-A Series
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78
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word, LEN=3, when one byte or <1byte, LEN=2 .
(5) DATA: <Data characters> data content. 2n ASCII compose n bytes, it have
fifty ASC II at most.
(6) LRC : longitudinal redundancy check
ASCII mode: Get LRC methods is that add ADDR to the last data, if the result
is more than 256,then the result subtract 256 until the result is less then 256 (if
the result is 128H, take 28H), then 100H subtract the result get LRC.
(7) For example: write 30.00Hz to inverter of 01 ( write to CD000 )
STX ADDR FUNC LEN DATA LRC END
“:”
“0”
“1”
“0”
“2”
“0”
“3”
“0” “0” “0”
“B” “B” “8”
“3” “7” “CR” “LF”
3AH 30H 31H 30H 32H 30H 33H 30H 30H 30H
42H 42H 38H
33H 37H 0DH 0AH
Calculate LRC: 01H+02H+03H+00H+0BH+B8H=C9H
C9H subtracted from 100H: 37H
So the sent data is following: 3AH 30H 31H 30H 32H 30H 33H 30H 30H 30H
42H 42H 38H 33H 37H 0DH 0AH
3.2 RTU Mode
Quiet ADDR FUNC LEN D
(n-1)
~D
(0)
CRC Quiet
>50ms >50ms
(1) Quiet: the time of no data is more than 50 ms
(2) ADDR: Communication address, 8-bit data
(3) FUNC: Function code, 8-bit data, refer to 3.1-3
(4) LEN: Data length, the length of D～n-1～~D0
(5) DATA: data content, n*8-bit
(6) LRC: Longitudinal Redundancy Check
RTU mode: get CRC～cyclical Redundancy Check～.
The CRC calculation method is following:
(1) make a 16-bit register and set value 0FFFFH(call CRC register)
(2) done first byte of data Exclusive OR with low byte of 16-bit CRC register
and save the result to CRC register
(3) done 1 bit right shift with CRC register and fill zero to left bit, then check
low bit of CRC register.
(4) if the low bit is zero, then do repeat setp3, else CRC register do Exclusive
OR with 0A001H.
(5) done repeat step 3 and 4,until CRC register done right shift 8 times, then the
byte is f ully done.
(6) done repeat step 2 to 5 for the next byte of data, until process completely