EMPROT Datasheet, PDF (6/17 Pages) rfsolutions.ltd – Micro RWD EM4102 Low Power Version

ib technology
Example a) NO card present, single STATUS (0x53) command received.
Note: at 9600 baud serial communication rate, a single byte is received or transmitted in
approximately 1mS (104µS per bit). If no commands follow then the polling rate reverts
back to the stored parameter value as in (1).
Command byte received +
6mS CTS timeout
CTS
Not to scale
7ms 10ms 6ms
1
Polling cycle period set by EEPROM
parameter (4ms to 8 seconds)
RWD
RX
2
(1ms) Command byte received
RWD
TX
3
Acknowledge byte reply
(1ms)
1 Host waits for CTS falling edge then sends command byte.
2 RWD processes command, RF turned ON for brief period to check if card present.
3 RWD then replies with acknowledge byte (+ data).
TTL levels
5v
0v
Polling cycle
repeats
5v
0v
5v
0v
Example b) EM4102 card in field, READ TAG (0x53 0x00) command received.
Command byte received +
6mS CTS timeout
CTS
Not to scale
8ms
21ms
6ms
1
100ms polling delay
(card still present)
RWD
RX
2
(2ms) Command byte + parameter received
TTL levels
5v
0v
Polling cycle
repeats
5v
0v
RWD
5v
TX
3
Acknowledge byte + 5 byte serial number reply
0v
15ms 6ms
6