Balluff BIS M-4008-048-0 ST4 PROFINET Series, Operating Manual

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BIS M-4008-048-0xx-ST4
PROFINET
17
Two buffers are needed to exchange data and commands between the processor unit and
the controlling system (input buffer and output buffer). The buffer contents are exchanged using
cyclical polling. The buffer content depends on the cycle in which it is written (e.g. control
commands at the beginning of a job).
When writing to the buffer, the transmitted data from the preceding cycle is overwritten.
Unwritten bytes are not deleted and retain their data content.
The control commands are carried over to the identification system and those on the data carrier
are carried over to written data through the output buffer.
Bit-No.
Subaddress
7 6 5 4 3 2 1 0
00
hex
= bit string TI KA GR AV
01
hex
Command identifier or Data
02
hex
Start address (Low Byte) or program No. or Data
03
hex
Start address (high byte) or Data
04
hex
Number of bytes (low byte) or Data
05
hex
Number of bytes (high byte) or Data
06
hex
Data
… Data
Last byte = bit
string
TI KA GR AV
Assignment and explanation
Subaddress Bit name Meaning Function description
00
hex
/last
byte
TI Toggle bit in Controller is ready to receive additional data
(read job).
KA Head shutoff Shuts off the R/W head's antenna. Tag
detection no longer takes place. CP and MT
are 0.
GR Basic state Cancels the current job for this R/W head
and puts the channel into a basic state. The
R/W head can then be used again once
GR = 0 and the controller has acknowledged
this with BB = 1. CP and MT are 0.
AV Job A job is present.
Note
After a R/W error the GR bit does not need to be set in order to place the R/W in the
basic state. Each time a command (successful or with error) is carried out, the R/W
head is in the basic state.
7.1 Function
principle of the
BIS M-4008
7.2 Process Data
Buffer
Output buffer
7
Device Function