EM4170
Memory Map
Bit15
Bit0
UM2 63
UM2 48
UM2 32
UM2 16
word 15
14
Bit
Bit 31
UM2 47
0
13 UM2 31
12 UM2 15
UM2
PIN 16
PIN
0
11
10
PIN 31
PIN 15
0
9
8
Crypt Key 95
Crypt Key 80
Crypt Key 64
Crypt Key 79
Crypt Key 48
Crypt Key 32
Crypt Key 16
Crypt Key 0
ID 16
7
6
5
Crypt Key 63
Crypt Key 47
Crypt Key 31
4
3
2
1
0
Crypt Key 15
ID 31
ID 15
ID 0
UM1 16
UM1 0
LB1,LB0,UM1 29
UM1 15
Fig. 4
Standby Mode
After a Power-On Reset and upon completion of a command, the chip will execute the Standby Mode, in which it will
continuously send LIWs to allow the reader to issue commands. As every LIW has a duration of 160 periods of the RF field
the reader can turn to Receive mode every 1.3ms at 125kHz.
Receive Mode
To change from Standby Mode to another operation the chip has to be brought into Receive Mode. To do this the
Transceiver sends to the chip the RM pattern during the 32 clocks of modulated phase in a Listen Window (LIW). The
EM4170 will stop sending data upon reception of a valid RM. The RM pattern consists of 2 bits "0" sent by the transceiver.
The first "0" is to be detected during the 32 periods when the modulation is "ON" in the LIW. Next the EM4170 expects a
command to specify the operation to be executed.
5
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