Processing Data Carriers - Balluff BIS C-60 3 Serie Handbuch

C60_3-025_825645_1310_e.p65
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Reading and writing
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Codetag Present
☞
Special
characteristics
Auto-Read
44 english
Function Description
Mode 1: Processing data carriers
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
1. The host sends to the output buffer:
– the command designator to subaddress 01
– the start address for reading or writing to subaddress 02
– the number of bytes for reading or writing to subaddress 04
– the CT bit in the bit header according to the data carrier type (block size),
– 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.
The toggle bits in the two bit headers are used as a kind of handshaking between the
host and the BIS C-60_3 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 of the input buffer and the AF bit in the bit header of the input
Hex
buffer will be set.
Function Description
Mode 1: Processing data carriers
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 31 bites or less if the buffer size has been set smaller).
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 input buffer, which is distributed over both heads when 2 are used.
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 les if the
buffer size has been set smaller).
50ff):
,
Hex
/03 ,
H H
EX EX
/05 ,
H H
EX EX
english
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