User's Manual

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english
Application
BIS L-405-... Processor
Restart when data
carrier is present
If a ReStart is detected while a data carrier is in the active zone of the read head, the data
outputs are switched to 0 and acknowledged with STR. As soon as ReStart goes low
again, first the STR signal is inverted as acknowledgement and the data carrier is read out
again. From there the process is the same as for a newly detected data carrier.
With this function you can force a re-read of a data carrier.
Timing
Data carrier
ReStart
TP
ADR
Data
STR
tx
t1 t1 t1 t1
t3
t2 t2
tx
t2 t2
Byte 0 Byte 1 Data value 0 Byte 0
tx = Read time ≈ 140 ms
t1 = Data output before Strobe ≈ 6 ms
t2 = Response to address change ≤ 15 ms
t3 = STR acknowledges ReStart finished ≈ 7 ms
BIS L-405-03_-00_-05-MU_834487_E_0709.p65
10
english10
Application
BIS L-405-... Processor
Restart with no data
carrier present
If a ReStart is detected when there is no data carrier in front of the read head, the data
outputs are switched to 0 and acknowledged with STR. The data from the last read data
carrier are deleted from the data memory and can no longer be read out. As soon as
ReStart is finished, a change in the STR signal acknowledges this.
You can use this function to re-synchronize data transmission.
Timing
t4
t1 t1 t1
t3t2 t2 t2
Byte n Byte n+1 Byte n+2 Data value 0
Data carrier
ReStart
TP
ADR
Data
STR
t1 = Data output before Strobe ≈ 6 ms
t2 = Response to address change ≤ 15 ms
t3 = STR acknowledges ReStart finished ≈ 7 ms
t4 = Tag Present 0 after removing the data carrier ≤ 60 ms