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2-1-2
BCC Calculation Example
The BCC (Block Check Character) is determined by calculating the exclusive OR of the bytes from the
node number up to ETX. The 8-bit result is written to the BCC byte at the end of the frame.
STX
Node number
02H
0 (30H) 0 (30H)
BCC = 30H+30H+30H+30H+30H+30H+35H+30H+33H+03H = 35H
The result of the calculation (35 hex) is written to the BCC byte.
The + symbols indicate XOR (exclusive OR) operations.
2-1-3
Response Frame
Node number Sub-address End code
STX
1
2
End code
Name
00
Normal completion
FINS command error
0F
Parity error
10
11
Framing error
Overrun error
12
BCC error
13
Format error
14
Sub-address error
16
Frame length error
18
• An end code is returned for each command frame received that was addressed to the local node.
• No response will be returned unless the frame contained all elements up to the ETX and BCC.
• "Error Detection Priority" indicates the priority when two or more errors occur simultaneously.
E5@D Digital Temperature Controllers Communications Manual (H225)
2 CompoWay/F Communications Procedures
SID
Sub-address
0 (30H) 0 (30H) 0 (30H) 0 (30H) 5 (35H) 0 (30H) 3 (33H)
0
0
2
2
Description
The command ended normally without error.
The specified FINS command could not be executed.
The FINS response code should indicate why the command
could not be executed.
The sum total of bits whose received data is "1" does not
match the set value of the "communications parity" bit.
Stop bit is "0."
An attempt was made to transfer new data when the
reception data buffer was already full.
The calculated BCC value is different from the received BCC
value.
• The command text contains characters other than 0 to 9,
and A to F. This error does not apply to Echoback Tests.
(Refer to 2-3-7 Echoback Test for details.)
• There was no SID and command text. There was no
command text.
• "MRC/SRC" not included in command text.
• Illegal (unsupported) sub-address
• There was no sub-address, SID, and command text.
• Sub-address was less than two characters, and there was
no SID and command text
The received frame exceeds the specified (supported)
number of bytes.
ETX
Command text
03H
BCC
Command text
ETX
1
BCC
35H
2
1
Error detection
priority
None
8
2
1
3
5
7
6
4
2 - 3
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