70016 Parallax Inc, 70016 Datasheet - Page 189

• Manufacturer Part Number: 70016
• Description: TEXT INFRARED REMOTE FOR BOE-BOT
• Manufacturer: Parallax Inc

Specifications of 70016

• Accessory Type: Manual
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: Boe-Bot®
• For Use With: 29122 - KIT PARTS IR REMOTE FOR BOE-BOT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Contains lead / RoHS non-compliant

should be either 1, 4, 8, or 16. For this activity, we'll go with 8, but the number of data
bits can be increased or decreased, simply by changing a couple lines of code. Here is
how the protocol will work:
TransmitCustomIrMessages.bs2 sends its messages as
circuit. The IR LED flashes on/off at 38 kHz for either 3, 2, or 1 ms. If this 38 kHz IR
flashing on/off shines on the IR receiver, it sends low signals while it detects that flashing
IR.
As a result of the flashing IR, the IR receiver will send low signals that last either 3, 2, or
1 ms.
ReceiveCustomIrMessages.bs2, measures these low signals with the
It then decodes these durations, storing the result as binary bits in a variable.
Testing IR Communication
TransmitCustomIrMessage.bs2 has some extra code in it that causes it to send a different
letter of the alphabet each time the Reset button on the board is pressed and released.
The sequence it will transmit is "a", "b", "c", ... "z". This program should be downloaded
to the BASIC Stamp on the board with the transmit circuit. This board can then be
disconnected from the serial cable. Then, the board with the receiver circuit can be
connected
ReceiveCustomIrMessages.bs2. After pointing the top of the IR LED at the face of the
IR receiver (see Figure B-1), each time the transmit board's Reset button is pressed and
released, the receiver board should display the character that was received and decoded in
the Debug Terminal.
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√
√
Pulses transmitted are least significant bit (LSB) first.
8 data bits are transmitted
A start bit is 3 ms
A binary-1 is 2 ms
A binary-0 is 1 ms
The minimum delay between pulses is at least 1 ms + any loop processing
overhead on the transmitter side.
The maximum delay between pulses is 0.131 s.
Connect the board with the IR transmitting circuit shown in Figure B-1 to the
Programming cable.
Download TransmitCustomIrMessage.bs2 to the transmitting BS2.
The BASIC Stamp module on the receiving end, which runs
(and
left
connected)
to
the
FREQOUT
serial
cable
commands to an IR LED
PULSIN
while
command.
running