Hitachi L300P - Manual (Page 242)

Communications Reference Information
Append
ix
B
B–16
Communications Reference Information
Inverter
Affirmative Reply The standard affirmative reply from the inverter
uses the ACK character (acknowledge) in the data
field. The frame format of this reply follows the
diagram and specification table.
Inverter
Negative Reply The standard negative reply from the inverter
uses the NAK character (negative acknowl-
edge) in the data field. The frame format of
this reply follows the diagram and specifica-
tion table.
The error codes for a NAK (negative acknowledge) are:
Element Description Size Value
STX Control code (STart of TeXt) 1 byte STX (0x02)
Node Node (station) address of inverter 2 bytes 01 to 32
ACK Control code (ACKnowledge) 1 byte ACK (0x06)
BCC Block check sum code 2 bytes Exclusive OR of Node and ACK
[CR] Control code (carriage return) 1 byte [CR] (0x0D)
STX Node ACK BCC [CR]
Frame format
Element Description Size Value
STX Control code (STart of TeXt) 1 byte STX (0x02)
Node Node (station) address of inverter 2 bytes 01 to 32
Data Error code – reason for negative
acknowledge 2 bytes (see error codes in next table)
NAK Control code
(Negative ACKnowledge) 1 byte NAK (0x15)
Error code Code representing error type 1 byte (See next table below)
BCC Block check sum code 2 bytes Exclusive OR of Node, Data,
and NAK
[CR] Control code (carriage return) 1 byte [CR] (0x0D)
Error
Code
Error Description
Error
Code
Error Description
01H Parity error 07H Receive buffer overrun error
02H Check sum error 08H Receive time-out error
03H Framing error 11H Abnormal command code error
04H Overrun error 13H Test error code
05H Protocol error 16H Abnormal parameter code/value error
06H ASCII code error — —
Node BCC [CR]
Frame format
STX NAK
Error
code