Components and Operation
English, Revision 04, Date: 19.01.2015
21
The antenna approaches a transponder:
-
voltages S and D increase
-
once the voltages S or D exceed the set „Threshold Decoding/Calculation“
1.
the counter „number of readings“ is reset to 0
2.
the status bit „TRANS_IN_FIELD“ (0x200) is set
-
codes are decoded and the counter „number of readings“ is incremented
1.
if the value is larger than „number of equal codes“, the status bit
„CODE_OK“ (0x400) is set and the code output.
2.
each decoded code now increases the counter „number of readings“
3.
if the value of „number of equal codes“ is = 0, each received code is output
4.
if the value of „number of equal codes“ is not = 0, the detected code is not
renewed
The antenna departs from a transponder:
-
voltages S and D decrease
-
once the voltages S or D fall below the set „Threshold Decoding/Calculation“, the
status bits „CODE_OK“ (0x400) and „TRANS_IN_FIELD“ (0x200) are reset
The counter „code readings“ stops, either whenever the line or column parities of the
code are wrong or no startsyncs were received. However, the bit „CODE_OK“ is
cleared only when the voltages U
s
and U
d
fall below the defined thresholds.
Normally, the value for „number of equal codes“ is set to a value > 0. In this case, the
code is only updated once, when the required number of equal codes was success-
fully decoded and then output without amendments until a new code is decoded at the
next transponder.
