User's Manual

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Data-carrier models
BIS L-20_-03/L
CT present
Model BIS L-20_-03/L data carriers have a unique serial number consisting of 5 bytes. These
are read-only and are considered like user data.
At CT Present the 5 bytes of the serial number are read from the data carrier and stored in the
Profibus input buffer (see
31). If the “Output data-carrier model and serial number at CT
present” function is enabled, model 03
Hex is output in Byte 1 of the input buffer and then the
5 bytes representing the unique serial number.
With model BIS L-20_-03/L data carriers, all data are read and output as soon as CT present
occurs. No other BIS L-60_2 processor commands are usable.
When using model BIS L-20_-03/L data carriers, set the following parameters:
Total buffer size on Profibus: 16 bytes
(8 bytes if only one read/write head is used)
Parameterizing bytes: 00
Hex 80Hex 00Hex 82Hex 00Hex 08Hex
or: 00Hex 80Hex 03Hex 82Hex 00Hex 08Hex
→ only model BIS L-20_-03/L data carriers are processed.
00
Hex 80Hex 00Hex 83Hex 00Hex 08Hex
→ output data carrier model and serial number at CT present.
Functions
Device parameters
Data carrier
BIS L-20_-03/L
L60_2-019_828132_1007-e.p65
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Function Description
Processing data carriers
Reading and writing
To carry out a read or write job, the data carrier must be located in the active zone of the
read/write head.
A read/write job has the following sequence (see examples on
37ff):
1. The host sends to the output buffer:
– the command designator to subaddress 01
Hex,
– the start address for reading or writing to subaddress 02
HEX/03HEX,
– the number of bytes for reading or writing to subaddress 04
HEX/05HEX,
– and sets the AV bit in the bit header to high.
2. The processor:
– takes the request (AA in the bit header of the input buffer to high),
– begins to transport the data;
read = from data carrier to input buffer,
write = from output buffer to data carrier.
(Larger data quantities are sent in blocks
block size with 2nd bit header = buffer size - 2,
block size without 2nd bit header = buffer size - 1).
The toggle bits in the two bit headers are used as a kind of handshaking between the
host and the BIS L-60_2 processor.
3. The processor has processed the command correctly (AE bit in the bit header of the input
buffer). If an error occurred during execution of the command, an error number will be
written to subaddress 01
Hex of the input buffer and the AF bit in the bit header of the input
buffer will be set.