User's Manual

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english
Start address for
Auto-Read
Function Description
Processing data carriers
Codetag Present
(CP bit)
As soon as the data carrier enters the active one of the read/write head, the processor indi-
cates this by setting the CP bit (Codetag Present).
To accelerate the reading of small amounts of data, the ID system makes the first bytes of the
data carrier available in the input buffer of the respective read/write head as soon as the tag is
detected. The number of bytes sent corresponds to the configured buffer size – 1 byte (2 bytes
for 2
nd
bit header).
If a model BIS L-20_-03L is present at the read/write head, a maximum of 5 bytes are output.
If the parameter “Output data-carrier model and serial number at CT Present” is set, the
data-carrier model and unique serial number are output instead of the read data. For model
BIS L-20_-03/L data carriers the read data correspond to the serial number.
The data are only valid after the rising edge of the CP bit in the bit header of the input buffer.
They remain valid until the falling edge of the CP bit, or until the controller issues a new job.
If the Auto-Read function is activated, the data are read starting with a specified start address
as soon as the data carrier is recognized. The rising edge of the CP bit is used to provide
these data in the input buffer. The start address must be specified for each head using
command identifier 07
Hex the start addresses may be different. The number of bytes read is
determined by the selected size of the input buffer, which is distributed over both heads when
2 are used.
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L60_2-019_828132_1007-e.p65
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Function Description
Processing data carriers
Reading and writing
in dynamic mode
In normal operation a read/write job is rejected by the BIS L-60_2 processor by setting the
AF bit and an error number if there is no data carrier in the active zone of the read/write head.
If dynamic mode is configured, the processor accepts the read/write job and stores it. When a
data carrier is recognized, the stored job is carried out.
Reading without simultaneous data transmission: In the case of a read job the processor
first reads our all requested data from the data carrier after receiving the start address and the
desired number of bytes, and then sets the AE bit. Then the data read from the data carrier
are written to the input buffer. In the case of larger data amounts this is done in blocks,
controlled by the handshake with the toggle bits as described on
30.
Reading with simultaneous data transmission: In the case of a read job the processor
begins by transmitting the data into the input buffer as soon as the first 30 bytes (with 2nd bit
header, or 31 bytes without 2nd bit header, or less if the buffer size was set smaller) have been
read from the data carrier beginning with the start address, and indicates this by inverting the
TO bit. As soon as the controller inverts the TI bit, the processor sends the data, which have
in the meantime been read, to the input buffer. This is repeated until the processor has read
out all the desired data from the data carrier. Now the processor sets the AE bit and outputs
the remaining data on the input buffer.
Writing without simultaneous data transmission: In the case of a write job the processor
waits until it has received all the data that need to be written from the controller. Only then are
the data written to the data carrier as described on
30.
Writing with simultaneous data transmission: In the case of a write job the processor
begins to write the data to the data carrier as soon as it has received the first data to be
written from the controller’s output buffer. Once all the data have been written to the data
carrier, the AE bit is set.
Reading and writing
with simultaneous
data transmission