Data Sheet

3 FM17520 Register Set
Datasheet
FM17520 Contactless Transceiver IC Ver 1.0 24
Bit
Symbol
Description
number of bytes in the FIFO buffer space is equal or less than the
defined number of WaterLevel bytes.
The bit LoAlert in Status1Reg is set to logic 1, if equal or less than
WaterLevel bytes are in the FIFO.
Tab3-27 WaterLevelReg bits description
3.2.1.13 ControlReg_address 0Ch
Some control bits.
Bit
7
6
5
4
3
2
1
0
Definition
TStopNow
TStartNow
RFU
RFT
RFU
RxLastBits
Access
Rights
w
w
-
-
-
r
r
r
Reset
Value
0
0
0
1
0
0
0
0
Tab3-28 ControlReg register
Bit
Symbol
Description
7
TStopNow
Set to logic 1, the timer stops immediately.
Reading this bit will always return 0.
6
TStartNow
Set to logic 1 starts the timer immediately.
Reading this bit will always return 0.
5
-
Reserved for future use.
4
RFT
Reserved for production tests.
3
-
Reserved for future use.
2-0
RxLastBits
Shows the number of valid bits in the last received byte. If 0, the
whole byte is valid.
Tab3-29 ControlReg bits description
3.2.1.14 BitFramingReg_address 0Dh
Adjustments for bit oriented frames.
Bit
7
6
5
4
3
2
1
0
Definition
StartSend
RxAlign
RFU
TxLastBits
Access Rights
w
r/w
r/w
r/w
-
r/w
r/w
r/w
Reset Value
0
0
0
0
0
0
0
0
Tab3-30 BitFramingReg register
Bit
Symbol
Description
7
StartSend
Set to logic 1, the transmission of data starts.
This bit is only valid in combination with the Transceive command.
6-4
RxAlign
Used for reception of bit oriented frames: RxAlign defines the bit position
for the first bit received to be stored in the FIFO. Further received bits are
stored at the following bit positions.
Example:
RxAlign = 0: the LSB of the received bit is stored at bit 0, the second
received bit is stored at bit position 1.
RxAlign = 1: the LSB of the received bit is stored at bit 1, the second
received bit is stored at bit position 2.
RxAlign = 7: the LSB of the received bit is stored at bit 7, the second
received bit is stored in the following byte at bit position 0.
This bit shall only be used for bitwise anticollision at 106 kbit/s in
Communication mode. In all other modes it shall be set to logic 0.
3
-
Reserved for future use.