EVAL-315-KEY2 Linx Technologies Inc, EVAL-315-KEY2 Datasheet - Page 2

• Manufacturer Part Number: EVAL-315-KEY2
• Description: RF Modules & Development Tools 2 Button Keyfob Eval Sys 315MHz
• Manufacturer: Linx Technologies Inc

Specifications of EVAL-315-KEY2

• Product: RF Development Tools
• Maximum Frequency: 315 MHz
• Supply Voltage (max): 3 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

OEM TRANSMITTER BUTTON ASSIGNMENTS
Figure 1: OEM Transmitter Button Assignments
RECEIVER / DECODER BOARD
Figure 2: OEM Basic Evaluation Kit Receiver / Decoder Board
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1.
2.
3.
4.
5.
6.
7.
8.
1
Battery - 3VDC (use 2 AAA style batteries only)
Power Switch
Buzzer - D0
LED - D1
Prototyping Area
KH2 Series Receiver Module
Reverse-Polarity SMA Antenna Connector
10-Position Address DIP Switch
CMD-HHCP-***
CMD-HHLR-***
CMD-HHTX-***
D7
D5
D3
D1
2
D6
D4
D2
D0
3
5
4
CMD-KEY#-***
D0
D3
D4
D1
D2
6
8
7
THEORY OF OPERATION
USING THE KIT
SETTING THE ADDRESS
OEM TRANSMITTERS
RECEIVER / DECODER EVALUATION BOARD
Linx OEM transmitters are a great way to quickly bring a remote control product
to market. They are fully assembled and certified, eliminating the need for
design, tooling, and certification. Linx can also customize the transmitters with
customer specific art, logos, or switch layouts.
The operation of the OEM transmitter is straightforward. When a button(s) is
pressed on the OEM transmitter, the states of D0 to D7 are formatted into secure
packets by an on-board encoder IC. These encoded packets are sent to a Linx
transmitter that, through the antenna, conveys the data into free space.
The receiver board is powered by two AAA batteries. A Linx KH2 Series receiver
is used for reception of the transmitted signal. This receiver provides exceptional
sensitivity, allowing the transmitter and receiver to operate at distances of up to
1,000 feet (depending on TX model and signal conditions). The data recovered
by the KH2 Series receiver is internally decoded. If the settings of the 10-position
DIP switch on the receiver board match the address setting of the transmitter, the
data lines are updated to match the state of the buttons on the OEM transmitter.
To demonstrate this, one data line on the evaluation board is used to drive a LED
while another is used to activate a buzzer. Transistors are used as drive buffers
since the KH2 receiver cannot directly source enough current for these devices.
Attach the antenna to the board, set the address on the transmitter and on the
board, turn on the power to the board, and press a button on the transmitter.
The Holtek encoder and decoder each have ten address lines that must match
in order for the transmitter and receiver to talk to each other. If they do not match,
then the decoder will ignore any transmission and take no action.
The address lines are tri-state, meaning that V
separate and valid states for the address. The OEM transmitters only make use
of the ground and floating states, so the receiver board is designed to match.
To set the address on the receiver evaluation board, note the A0 - A9 labels on
the board and turn the DIP switches on or off as desired. If a switch is on, the
address line is connected to ground. If it is off, then the address line is floating.
The four OEM transmitters have different ways of setting their address lines. For
your convenience, a brief explanation follows; however, the OEM transmitter
manual or Application Note AN-00300 should be referenced for complete details.
The HHTX has an eight-position DIP switch accessed by opening the case.
Switch number 8 corresponds to A0 and number 1 corresponds to A7. A8 and
A9 are floating on the transmitter and must be left off on the receiver board.
The HHCP and HHLR utilize a ten-position DIP switch that is accessed by a
cover on the back of the remote. The switch numbers match the address lines
with switch number 1 corresponding to A0 and number 10 to A9.
The Keyfob has ten internal cut traces numbered 0 to 9 to match A0 to A9. If the
trace is intact, it is connected to ground; when cut, it is floating.
CC
, ground, and floating are
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