pic to pic ir link versus wired link : help please anyone

[xnihilo]

It should work. But you probably need to invert it.

On the transmit side, where it would previously turn the HPWM ON, make the pin LOW instead.

For PWM OFF, set the pin HIGH, and forget the transistor.

Added: And make sure the CCP module is turned OFF.
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Yes, turn it low instead of high because I have to pull low my receiver pic pin RA0 to trigger the int.

But, and wouldn't it be better, I can also output a positive voltage pulse while the receiver pic is pulled to GND by a WPD resistor and PULSIN listens to a Low to HIGH transition: PULSIN porta.0,1,etcetera

IF (a.0(0) == 0) THEN
    FOR i = 0 to 13                     'get a sequence of incoming 14 bits (WITHOUT their prefixes which are 600us pause)
        PULSIN PORTA.0,1,ir_pulse[i]    ' Read 14 low-going pulses on RA.4, see pbp manual
    NEXT i
    pin = 0                              ' Loop 14 times, record in 5us resolution pulse duration in the word variables array
ENDIF

It would work too?

BTW, why do I need to disable CCP module? It would prevent the output to work fine?


And what's technicaly wrong with using a transistor???

[mister_e]

As long as MAX 25mA drive to the LED give you enough range... there's no 'real' need for the extra transistor.

[xnihilo]

As long as MAX 25mA drive to the LED give you enough range... there's no 'real' need for the extra transistor.

The IR led I use in the 'gun' module is boosted at 1A (!!!) so I have to use a HEXFET.
Anyway, for the "Supplier module", it is only to send a 14bits message and as I wrote above, to avaoid cheating, I really need to use a wired link instead of IR link. So I have to avoid using IR link.

[skimask]

As long as MAX 25mA drive to the LED give you enough range... there's no 'real' need for the extra transistor.

Except for the 'heating/burning' pads...

[xnihilo]

Except for the 'heating/burning' pads...

gimme a break willya

[Darrel Taylor]

BTW, why do I need to disable CCP module? It would prevent the output to work fine?

Yes, as long as the CCP module is ON, it has control of the CCP1 pin.

And what's technically wrong with using a transistor???

Nothing really. Just extra parts that don't add any functionality.

But after thinking a little more about it ...
With people that are running and jumping with nylon backpacks while wearing rubber soled shoes ... If the first contact between 2 of them is going to be the connection to deliver a health pack? I think extra ESD protection on those pins would be the biggest concern.
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[xnihilo]

Yes, as long as the CCP module is ON, it has control of the CCP1 pin.


Nothing really. Just extra parts that don't add any functionality.

But after thinking a little more about it ...
With people that are running and jumping with nylon backpacks while wearing rubber soled shoes ... If the first contact between 2 of them is going to be the connection to deliver a health pack? I think extra ESD protection on those pins would be the biggest concern.
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jeeze... i didn't think about that.
the pics don't have some esd protection like the eeproms (24lc08 seem to have that)?
How can i prevent an esd? using a capacitor?