Hitachi SJ700-2 instruction manual Ii Negative response Response frame Frame format

Chapter 4 Explanation of Functions

(2)Positive and negative responses

(i) Positive response - Response frame Frame format

STX

Station No.

ACK

BCC

CR

	Description	Data size	Setting
STX	Control code (Start of TeXt)	1 byte	STX (0x02)
Station No.	Station number of control-target	2 bytes	01 to 32
	inverter
ACK	Control code (acknowledgement)	1 byte	ACK (0x06)
BCC	Block check code	2 bytes	XOR of the items from "Station No." to "ACK."
			See Item (3) of this section.
CR	Control code (Carriage Return)	1 byte	CR (0x0D)

(ii)Negative response - Response frame Frame format

STX

Station No.

NAK

Error code

BCC

CR

	Description	Data size	Setting
STX	Control code (Start of TeXt)	1 byte	STX (0x02)
Station No.	Station number of control-target	2 bytes	01 to 32
	inverter
NAK	Control code (negative	1 byte	NAK (0x15)
	acknowledgement)
Error code	Content of communication error	2 bytes	See Note 13.
BCC	Block check code	2 bytes	XOR of the items from "Station No." to "Error
			code." See Item (3) of this section.
CR	Control code (Carriage Return)	1 byte	CR (0x0D)

Note 15: Error codes

Error code	Description
01H	Parity error
02H	Sum check error
03H	Framing error
04H	Overrun
05H	Protocol error
06H	ASCII code error
07H	Receiving-buffer overflow
08H	Reception timeout
-	-
-	-
11H	Command error
12H	-
13H	Execution disabled
14H	-
15H	-
16H	Parameter error
17H	-

If a command is broadcasted to all inverter stations, no response will be returned to the external control system.

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