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LFM 4x Reader Rev1.4
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49
Customer manual
LFM 4x Reader
RFID
WE GENERATE SOLUTIONS
When reading several pages (par. 1:
readmode
„tag“ or „everything“) the command is repeated
for each read page. The last package contains the command
‚R‘ and the reader ID.
The host expects a confirmation of the read data. If there is no confirmation from the host, the
command is repeated. (par.5:
‚RS232 repeat time‘
, par.6:
‚RS232 maxrepeat‘
).
If a reading is not possible, the reader automatically repeats the reading with the set
parameters. (par.3:
‚r / w delay time‘
, par.4
‚r / w maxrepeat‘
).
If no reading is possible,
the reader sends the error message ‚no tag (4)‘ to the host.
The delay time for the presence sensor can be set (parameter 0:
‚sensor delay‘
).
An automatic reading is only possible if all messages to be confirmed have been confirmed by
the previous reading or the waiting time (par.5:
‚RS232 repeat time‘
, par.6:
‚RS232 maxrepeat‘
)
has elapsed after the last transmission.
10.4.3 W - Write data
The command W starts writing a defined data area of a transponder.
If there is no transponder in the write range of the antenna, the reader sends an
error message (error 4 - no transponder).
Host
Device
CMD
Reader-ID
Page
Data
W
1 Byte
2 Bytes
16 Bytes
Device
Host
CMD
Reader-ID
w
1 Byte
If the describing of the tag fails, the reader repeats the writing operation several times before
sending an error message. The number of repetitions is defined in parameter 4 (
‚r / w
maxrepeat‘
). If writing is still not possible, the reader sends the error message
‚no tag (4)‘ to the
host after the repetitions have been carried out.
If the sensor check is activated (parameter 1:
readmode
), the assignment of the external input
is checked before the start of the write process by the host. The write process is started only
when the sensor is busy, otherwise the error message
‚no tag (4)‘ is sent.
