Balluff BIS V-6111 series, Техническое описание, Руководство пользователя

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BIS V-6111 CC-Link
Processor unit
19 english
The CRC check is a procedure for determining a check value for data in order to be able to
recognize transmission errors. If the CRC check is activated, an error message is sent when a
CRC error is detected.
Checksum
M and L system:
The checksum is written to the data carrier as 2 bytes of information. 2 bytes per block are lost.
This leaves 14 bytes per block available. The usable number of bytes can be found in the follow-
ing table.
C system:
The checksum is written to the data carrier as 2 bytes of information per page.
2 bytes per page are lost, i.e. the page size is 30 bytes or 62 bytes depending on the
data carrier type.
The number of usable bytes thus decreases when using the checksum.
Balluff data carrier type Memory capacity Usable bytes for
CRC_16
BIS M-1_ _-
01
752 bytes 658 bytes
BIS M-1_ _- 02 2000 bytes 1750 bytes
BIS M-1_ _- 03 112 bytes 98 bytes
BIS M-1_ _-
04
256 bytes 224 bytes
BIS M-1_ _- 05 224 bytes 196 bytes
BIS M-1_ _- 06 288 bytes 252 bytes
BIS M-1_ _-
07
992 bytes 868 bytes
BIS M-1_ _- 08 160 bytes 140 bytes
BIS M-1_ _- 09 32 bytes 28 bytes
BIS M-1_ _-
10
736 bytes 644 bytes
BIS M-1_ _- 11 8192 bytes 7168 bytes
BIS M-1_ _- 13 32786 bytes 28672 bytes
BIS M-1_ _- 14 65536 bytes 57344 bytes
BIS M-1_ _- 15 131072 bytes 114688 bytes
BIS M-1_ _-
20
8192 bytes 7168 bytes
BIS L-1_ _- 01 192 bytes 168 bytes
BIS L-2_ _- 03 5 bytes (read-only) —
BIS L-1_ _-
05
192 bytes 168 bytes
BIS C-1_ _- 04 511 bytes 450 bytes
BIS C-1_ _- 05 1023 bytes 930 bytes
BIS C-1_ _-
11
2047 bytes 1922 bytes
BIS C-1_ _- 32 8192 bytes 7936 bytes
To use the CRC check, the data carrier has to be initialized. Initialization of the data carrier is
accomplished in the output buffer using the command designator 12
hex
. If the data carrier does
not contain the correct CRC, the processor unit sets an error message in the input buffer (see
Example 7 on page 50).
Data carriers as shipped from the factory can be written immediately with a checksum, since all
data is set to 0.
CRC check
Initializing
6
Startup