FT1A S
MART
A
XIS
U
SER
’
S
M
ANUAL
FT9Y-B1382
25-17
25: U
SER
C
OMMUNICATION
I
NSTRUCTIONS
BCC (Block Check Character)
The SmartAxis has an automatic BCC calculation function to detect a communication error in incoming data. If a BCC code is
designated in the receive format of a RXD instruction, the SmartAxis calculates a BCC value for a specified starting position
through the position immediately preceding the BCC and compares the calculation result with the BCC code in the received
incoming data. The start position for the BCC calculation can be specified from the first byte through the 15th byte. The BCC can
be 1 or 2 digits.
When an end delimiter is not used in the RXD instruction, the BCC code must be positioned at the end of the receive format
designated in Source 1 device. When an end delimiter is used, the BCC code must be immediately before or after the end delimiter.
The SmartAxis reads a specified number of BCC digits in the incoming data according to the receive format to calculate and
compare the received BCC code with the BCC calculation results.
BCC Calculation Start Position
The start position for the BCC calculation can be specified from the first byte through the 15th byte. The BCC is calculated for the
range starting at the designated position up to the byte immediately before the BCC of the receive data.
Example: Received data consists of 17 bytes plus 2 BCC digits.
(1) Calculation start position = 1
(2) Calculation start position = 2
BCC Calculation Formula
BCC calculation formula can be selected from XOR (exclusive OR), ADD (addition), ADD-2comp, Modbus ASCII, or Modbus RTU.
Example: Incoming data consists of 41h, 42h, 43h, and 44h.
(1) BCC calculation formula = XOR
Calculation result = 41h
42h
43h
44h = 04h
(2) BCC calculation formula = ADD
Calculation result = 41h
42h
43h
44h = 10Ah
0Ah (Only the last 1 or 2 digits are used as BCC.)
(3) BCC calculation formula = ADD-2comp
Calculation result = FEh, F6h (2 digits without conversion)
(4) BCC calculation formula = Modbus ASCII
Calculation result = 88 (ASCII)
(5) BCC calculation formula = Modbus RTU
Calculation result = 85h 0Fh (binary)
STX
BCC calculation range
1st
“A”
2nd
“B”
3rd
“C”
4th
“D”
5th
“E”
6th
“0”
15th
CR
16th
LF
17th
BCC
18th
BCC
19th
BCC
(2 digits)
STX
BCC calculation range
1st
“A”
2nd
“B”
3rd
“C”
4th
“D”
5th
“E”
6th
“0”
15th
CR
16th
LF
17th
BCC
18th
BCC
19th
BCC
(2 digits)
Содержание microsmart pentra
Страница 1: ...FT1A SERIES FC9Y B1382 Ladder Programming Manual ...
Страница 6: ...Preface 5 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Страница 104: ...7 DATA COMPARISON INSTRUCTIONS 7 10 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Страница 122: ...8 BINARY ARITHMETIC INSTRUCTIONS 8 18 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Страница 138: ...10 SHIFT ROTATE INSTRUCTIONS 10 12 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Страница 162: ...11 DATA CONVERSION INSTRUCTIONS 11 24 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Страница 188: ...12 CALENDAR COMPARISON INSTRUCTIONS 12 26 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Страница 198: ...15 REFRESH INSTRUCTIONS 15 4 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Страница 202: ...16 INTERRUPT CONTROL INSTRUCTIONS 16 4 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Страница 266: ...20 DUAL TEACHING TIMER INSTRUCTIONS 20 4 FC5A MICROSMART USER S MANUAL FC9Y B1273 ...
Страница 318: ...25 USER COMMUNICATION INSTRUCTIONS 25 22 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...