gefran VDI100 User Manual

Data Frame for RTU Mode
Master (PLC etc.) sends request to follower (inverter), and the follower sends a response to the master (PC,
PLC). The data received is illustrated here.
The data length varies depending on the command (Function).
Node Address
Function Code
DATA
CRC CHECK
Signal Interval
** The inverter response time is 10ms.
Node Address
00H: Broadcast to all the drivers
01H: to the No. 01 inverter
0FH: to the No.15 inverter
10H: to the No.16 inverter and so on...., max to No. 254 (FEH)
Function Code
03H: Read the register contents
06H: Write a WORD to register
08H: Loop test
10H: Write several data to register (complex number register write)
Checksum Calculation
LRC
ex. NODE ADDRESS 01H
FUNCTION 03H
COMMAND 01H
00H
+ DATA LENGTH 0AH
------------------------------------------
0FH ------------ 2’s complement
Checksum F1H
CS (H) 46H (ASCII)
CS (L) = 31H (ASCII)
CRC
CRC Check: CRC code covers the content from node address to DATA. Please calculate it according to the
following methods.
(1) Load a 16-bit register with FFFF hex (all1’s). Call this CRC register.
(2)ExclusiveORtherst8-bitbyteofthemessage,thelow-orderbyteofthe16-bitCRCregister,puttingthe
result in the CRC register.
(3)ShifttheCRCregisteronebittotheright(towardtheLSB),Zero-llingtheMSB,Extractandexaminesthe
LSB.
(4) (If the LSB was 0): Repeat Steps (3) (another shift)
(If the LSB was 1): Exclusive OR the CRC register with the polynomial value A001 hex (1010 0000 0000 0001),
putting the result in CRC register.
(5) Repeat Steps (3) and (4) until 8 shifts been performed. When this is done, a complete 8-bit byte will be
processed.
(6) Repeat Steps (2) through (5) for next 8-bit byte of the message, Continue doing this until all bytes have
beenprocessed.ThenalcontentintheCRCregisteristheCRCvalue.WhensendingtheCRCvalue,
theLow-orderbyteshouldbesentrstly,thentheHigh-orderbyte.Forexample,CRCvalue:1241Hex,the
high-order byte should be set to 41hex and low-order byte 12hex.
6 VDI100 • Instruction manual

gefran VDI100 Specifications

General

Brand	gefran
Model	VDI100
Category	Motherboard
Language	English