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Reading and writing
in dynamic mode
In normal operation a read/write job is rejected by the BIS C-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 proces-
sor 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 29.
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 proces-
sor 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 29.
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
Function Description
Processing data carriers
C60_2-019_818217_0806-e.p65
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Mixed Data Access
Function Description
Processing data carriers
Small read/write programs can be stored in the BIS C-60_2 processor’s EEPROM.
The Mixed Data Access function is useful when the required information is stored on the
data carrier at various addresses. This function makes it possible to read out this “mixed”,
i.e. non-contiguously stored data from the data carrier in a single procedure and using just
one command.
Up to 10 programs with up to 25 instructions can be stored. Each program instruction con-
tains a “start address” and a “number of bytes” specification. The amount of data for reading
may not exceed 2 kB.
Storing a program:
The command identifier 06
Hex
is used to send the read/write program to the BIS C-60_2 pro-
cessor. One program per command can be stored. All 25 program records plus an additional
2 bytes with FF
Hex
FF
Hex
as a terminator must always be sent. This means a total of
104 bytes
of information per program must be sent (including the command identifier and program num-
ber).
The individual program records must all be contiguous. They must be sent one after the other
and be terminated with 2 bytes FF
Hex
FF
Hex
as a terminator. It is recommended that the remaining,
unused memory sector be filled with FF
Hex
FF
Hex
.
If an address range is selected twice, the data will also be output twice.
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