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Special
characteristics
Function Description
Mode 2: Processing data carriers
Codetag Present
As soon as the data carrier enters the active one of the read/write head, the processor
indicates 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 corresponds to the parameter
Input length,
with a maximum of
31 bytes.
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.
To adjust the read/write functions to the numerous possible applications, a few unique fea-
tures have been implemented that the user can select and set when parametering or program-
ming the processor. These are as follows:
If Auto-Read is enabled, data are read beginning from a start address as soon as a data
carrier is recognized. The start addresses for Head 1 and Head 2 may be dcifferent and are
determined when parametering. The number of bytes read is determined by the selected size
of the parameter
Input length 1
(for Head 1) or
Input length 2
(for Head 2).
This distinguishes the Auto-Read function from the standard setting for automatic reading,
which always starts at Address 0 and includes a maximum number of 31 bytes (or less if the
parameter
Input length 1
has been set smaller).
☞
Auto-Read
C60_3-025_825645_1310_e.p65
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Function Description
Mode 2: Processing data carriers
Reading and writing
in dynamic mode
In normal operation a read/write job is rejected by the BIS C-60_3 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.
CRC initialization is not possible in Mode 2.
CRC initialization
