CHAPTER 2 CompoWay/F COMMUNICATIONS PROCEDURES
H8GN
2-2
2.1 Data Format
Unless otherwise indicated, numbers in this manual are expressed in hexĆ
adecimal. Values in double quotation marks, such as 00", are ASCII.
The numberunderneath each delimiterin a frame indicates the number
of bytes.
JCommand frame
STX
0
0
ETX
1
2
2
1
1
1
BCC
SID
Text
BCC calculation range
Node No.
SubĆaddress
Command text
0
STX
This code (02) indicates the beginning of the communications frame (text).
Always set this character in the first byte.
When STX is received again during reception, reception is carried out again from
the point where STX was received.
Node number
•
This number specifies the transmission's destination.
•
Specify the H8GN's Communications unit No.".
•
BCD range 00" to 99" and XX" can be set.
•
Specify XX" for a broadcast transmission. No response will be returned for broadĆ
cast transmissions.
•
No responses will be returned from node Nos. set otherwise from the above.
SubĆaddress
This is not used on the H8GN. Be sure to set the subĆaddress to 00".
SID (service ID)
This is not used on the H8GN. Be sure to set the subĆaddress to 00".
Command text
Command text area. For details, see 2.2 Structure of Command Text."
ETX
This code (03) indicates the end of the text.
BCC
Block Check Character
The BCC result is found by calculating the exclusive OR of the bytes from the node
No. up to ETX.
