Data Sheet

3 FM17520 Register Set
Datasheet
FM17520 Contactless Transceiver IC Ver 1.0 30
3.2.2.8 RxSelReg_address 17h
Select internal receiver settings.
Bit
7
6
5
4
3
2
1
0
Definition
UartSel
RxWait
Access Rights
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
Reset Value
1
0
0
0
0
1
0
0
Tab3-50 RxSelReg register
Bit
Symbol
Description
7-6
UartSel
Selects the input of the contactless UART
Value
Description
00
Constant Low
01
Manchester with subcarrier from pin TIN
10
Modulation signal from the internal analog module, default
11
NRZ coded signal without subcarrier from pin TIN which is
only valid for transfer speeds above 106 kbBd
5-0
RxWait
After data transmission, the activation of the receiver is delayed for
RxWait bit-clocks. During this ‘frame guard time’ any signal at pin RX is
ignored. This parameter is ignored by the Receive command. All other
commands use this parameter. The counter starts with the last
modulation pulse of the transmitted data stream.
Tab3-51 RxSelReg bits description
3.2.2.9 RxThresholdReg_address 18h
Select thresholds for the bit decoder.
Bit
7
6
5
4
3
2
1
0
Definition
MinLevel
RFU
CollLevel
Access Rights
r/w
r/w
r/w
r/w
-
r/w
r/w
r/w
Reset Value
1
0
0
0
0
1
0
0
Tab3-52 RxThresholdReg register
Bit
Symbol
Description
7-4
MinLevel
Defines the minimum signal strength at the decoder input that shall be
accepted. If the signal strength is below this level, it is not evaluated.
3
-
Reserved for future use.
2-0
CollLevel
Defines the minimum signal strength at the decoder input that has to
be reached by the weaker half-bit of the Manchester-coded signal to
generate a bit-collision relatively to the amplitude of the stronger
half-bit.
Tab3-53 RxThresholdReg bits description
3.2.2.10 DemodReg_address 19h
Define demodulator settings.
Bit
7
6
5
4
3
2
1
0
Definition
AddIQ
FixIQ
RFU
TauRcv
TauSync
Access Rights
r/w
r/w
r/w
-
r/w
r/w
r/w
r/w
Reset Value
0
1
0
0
1
1
0
1
Tab3-54 DemodReg register