Linx Technologies EVAL-xxx-LT - Manual (Page 5)

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Development Using the Prototyping Area
In addition to their evaluation functions, the boards may also be used for
product development. They feature a prototyping area to facilitate the
addition of application-specific circuitry. This area has a connection to V
CC
at the bottom and to ground at the top which can be used to power any
added circuitry.
The holes are plated and set at 0.1" on center with a 0.04" diameter,
making it easy to add most industry-standard SIP and DIP packages to the
board.
All of the lines from the transceiver have been wired out to a row of plated
holes on the right side of the prototyping area. Four of the data lines from
the transcoder have also been wired out. This allows for easy access to
connect external circuitry to the modules and the transcoder. Three lines
from the transceiver (DATA, T/R_SEL, and PDN) have been routed to
switches. The switches connect the lines to either the transcoder or the
prototyping area. This allows the transceiver to be conveniently switched
between the transcoder and application circuitry during testing.
Note: If added circuitry requires a higher current than can be provided
by the batteries, the batteries must be removed and the board powered
from an external source.
Theory of Operation
The two transceiver evaluation boards are identical, but they are populated
slightly differently. The MT Series transcoder is both an encoder and a
decoder, with the input or output nature of each line being determined by
how the board is populated. One board has buttons S0 and S1 populated,
making those lines inputs. On the other board, those lines are connected
to the buzzer and LED, respectively. Conversely, the first board has lines
D2 and D3 connected to the buzzer and LED, while the second board has
buttons S2 and S3 populated. This allows for bidirectional remote control.
To use the kit, simply attach the antennas, turn on the power, and press
one or both of the buttons on a board. When S0 or S2 is pressed, the
buzzer sounds; when S1 or S3 is pressed, the LED turns on.
Both boards have a confirmation LED. When one transcoder sends a
command to the second transcoder, the second transcoder sends a
confirmation back to the first transcoder indicating that the command was
received and the action performed. When the first transcoder receives the
confirmation, it turns on the CONFIRM LED to indicate this. This feature
offers the ability to range test without needing to be in visual or hearing
range of both boards.
The MT Series Transcoder Data Guide goes into the many features of the
transcoders in detail, but this is the only set-up required for operation of
this kit.
Using the Kit
Using the kit is straightforward. Simply attach the antennas, turn on the
power, and press buttons on one of the boards. When S0 or S2 is pressed,
the LED turns on; when S1 or S3 is pressed, the buzzer sounds. When any
button is pressed, the CONFIRM LED lights up to indicate that the other
side got the command.