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CircuitGizmos

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Joined: 08/09/2011
Location: United States
Posts: 1427

Posted: 10:20pm 22 Dec 2020

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As far as I can determine, a CMM2 cannot transmit IR to itself.

Is it deliberate that the IR receive function is suspended during the IR transmision?

Micromites and Maximites! - Beginning Maximite

JoOngle
Regular Member

Joined: 25/07/2020
Location: Sweden
Posts: 82

Posted: 11:26pm 22 Dec 2020

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Well, the CMM2 comes with an IR Diode or IR transistor (depending on model I guess), but - since it doesn't have a SEPARATE IR diode (aka, only one) there's no reason for it to read and transmit at the exact same time, but I guess you could switch really fast between reading and transmitting.

The LED can't receive light while transmitting light...if that makes any sense to you?

You could solve this by adding another IR led to one of the many input pins and use that one to read/write while the main IR is doing the opposite of that, then you have Full Duplex IR transmission.

CircuitGizmos

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Joined: 08/09/2011
Location: United States
Posts: 1427

Posted: 11:36pm 22 Dec 2020

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I'm using a RetroMax version of the CMM2.

It has (comes with) an IR receiver onboard (on PB12).

This is the IR Sample code:

IR DevCode, KeyCode, IR_Int ' start the IR decoder
DO
' < body of the program >
LOOP
SUB IR_Int ' a key press has been detected
PRINT "Received device = " DevCode " key = " KeyCode
END SUB

This code happily decodes an external remote control.

Then I added IR SEND 40, 1, 10 and the appropriate transistor and IR LED.

I had expected the IR example code to still receive the transmitted signals. The 1/10 combination is not received.

(Another CMM2 running the code does receive)

Micromites and Maximites! - Beginning Maximite

vegipete

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Joined: 29/01/2013
Location: Canada
Posts: 1132

Posted: 12:14am 23 Dec 2020

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I presume you tested if it will receive an external IR signal while transmitting?

Visit Vegipete's *Mite Library for cool programs.

CircuitGizmos

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Joined: 08/09/2011
Location: United States
Posts: 1427

Posted: 06:08pm 23 Dec 2020

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I didn't make an effort to send IR during the exact moment that the IR SEND routine was running. Touching the button on my remote could happen during the send or during the intervals between.

The reason for this was to have a board on the rPi port with an IR LED and the operation of that LED would have been tested by receiving the transmitted signal.

Micromites and Maximites! - Beginning Maximite

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