Communication Between Communication Module, Reader And Transponder - Siemens SIMATIC RF 300 System Manual

4.1.7

Communication between communication module, reader and transponder

Communication with RF 310-R
Communication between the communication module (IQ Sense), RF 310-R reader and
transponders takes place in fixed telegram cycles. 3 cycles of approximately 3 ms are
always needed for the transfer of a read or write command. 1 or 2 bytes of user data can be
transferred with each of these commands. The acknowledgement transfer (status or read
data) takes place in 3 further cycles. Approximately 18 ms are thus needed for a complete
command acknowledgement sequence with up to 2 bytes of user data. The transponder
must be present within the field of the reader.
Calculation of the communication time for interference-free transfer
t
K
Calculation of the maximum amount of user data
n
t
K
t
V
n
n
max
t
Word
K
Note
If only 1 byte of user data is transferred, you still need to allow the time for 1 word.
RF 300
System Manual, 05/2005, (4)J31069 D0166-U001-A1-7618, --
= + ⋅
K t n
Wort
−
t K
v
=
max
t
Wort
Communication time between communication module, RF 310-R (IQ-Sense) reader and
transponder
Dwell time
Amount of user data in words (2 bytes)
Max. amount of user data in words (2 bytes) in dynamic mode
Transfer time for 1 word (2 bytes)
Constant (internal system time) This contains the time for power buildup on the transponder
and for command transfer
RF 300 system planning
4.1 Fundamentals of application planning
4-7