Table 5: Counter Definition For Pulse Position Demodulation; Wake Pattern Detection Flag 'No_Wake; Write Distance Expander 2 Flag 'No_Wde2; Write Distance Expander 3 Flag 'No_Wde3 - Texas Instruments TRIS TMS37122 Reference Manual

August '01

2.10.3.4 Wake Pattern Detection Flag 'NO_WAKE'

2.10.3.5 Write Distance Expander 2 Flag 'NO_WDE2'

2.10.3.6 Write Distance Expander 3 Flag 'NO_WDE3'

2.10.3.7 CLKA Output Disable Flag 'NO_CLKA'
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Table 5: Counter Definition for Pulse Position Demodulation

Pulse Position Modulation
DEC Chdet
0
1 8
2 16
3 24
4 32
5 40
6 48
7 56
8 64
9 72
10 80
11 88
12 96
13 104
14 112
15 120
If the NO_WAKE flag is set no Wake Pattern check is performed and the Control Unit
switches directly to Transparent Mode if VWAKE-A threshold is exceeded.
If the NO_WDE2 flag is set the Wake Detector of RF2 input is completely disabled. The RF2
input should be connected to VCL externally in this case. Standby current consumption is re-
duced due to this.
If the NO_WDE3 flag is set the Wake Detector of RF3 input is completely disabled. In this
case the RF3 input should be connected to VCL externally. Standby current consumption is
reduced due to this.
If the NO_CLKA flag is set, the CLKA/M output does not provide a clock when WAKE is
activated. This prevents back coupling of interference to the sensitive RF inputs due to not
optimized PCB layout.
The option can be used at identification devices, which do not require the CLKA. This is the
case, if the microcomputer is able to measure period duration or if the data (EOBA) includes
Thdet Nom.[µs]
- -
59
119
179
238
298
358
417
477
537
596
656
715
775
112
894
Chapter 2. Electrical Description
PPM Threshold
MSB
0 0 0
0 0 0
0 0 1
0 0 1
0 1 0
0 1 0
0 1 1
0 1 1
1 0 0
1 0 0
1 0 1
1 0 1
1 1 0
1 1 0
1 1 1
1 1 1
LSB
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1