User's Manual

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RF Digital Corp.
9/2/2010 12:02 PM
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RFDP8
RFDANT
RFD21743
Eval Board
RFD21773
6 IN2 Input Active high switch input #2 (optional) if not used, pull to GND.
7 IN3 Input Active high switch input #3 (optional) if not used, pull to GND.
When all three switch inputs are low, the module does not transmit, but remains in an ultra-low-power state
consuming only 2uA.
When any of the three switch inputs go high, the module transmits the state of all three inputs. As long as any of
the three inputs remain high, the module continues to transmit the state of all three inputs every 15ms, while
transmitting it will draw about 15mA.
You can also tie any of the three inputs to +V and then connect a switch between +V of the module and your
supply, then once you apply +V to the module it will instantly transmit as fast as possible, this is the method can
be used to consume zero current when not in use such as in the case of garage door openers or keyfobs and can
be used for many years without consuming any current at all.
Modes 2 – 9600 baud UART
Pin # Pin Label Direction Function
13 +V Input +V Power
10 GND Input Ground
16 Mode Select 0 Input Tie to GND
17 Mode Select 1 Input Tie to +V
3 Mode Select 2 Input Tie to GND
4 Not Used Output Do not connect, not used.
5 Logic IO I/O Bidirectional switch logic I/O, if not used, pull to GND.
6 RXD Output RX Data Out, UART output of received data.
7 TXD Input TX Data In, UART input of data to transmit.
Modes 3 – 9600 baud UART (Network)
Pin # Pin Label Direction Function
13 +V Input +V Power
10 GND Input Ground
16 Mode Select 0 Input Tie to +V
17 Mode Select 1 Input Tie to +V
3 Mode Select 2 Input Tie to GND
4 Learn / Status I/O Pulse high to enter learn mode and LED Learn Status Output.
5 Logic IO I/O Bidirectional switch logic I/O, if not used, pull to GND.
6 RXD Output RX Data Out, UART output of received data.
7 TXD Input TX Data In, UART input of data to transmit.
9600 baud half-duplex UART, suitable for connection to a microcontroller, or a level translator (such as a
MAX202) to an RS-232 port. RF transmission takes priority over RF reception, so that a module will not receive
anything over the air if it is given a full-speed stream of serial data on TX_in.