Ok here is what I need to do...
I must use the palm pilot to emulate a security system keypad...
In the security system... the keypad is slave so it listen on the BUS
using I2C Bus protocol, to receive lit leds and to input pressed keys.

I must plug the palm pilot serial to the security system bus and emulate the
keypad..
To do so... I must be able to listen on the BUS to syncronise...
The syncronisation mechanisim is simple...

On the I2C Bus protocol there is two wire DATA and CLOCK
I must listen on the Clock... when I catch a 32 ms delay between impulse
This means Im at the begining of the sequence.. so now Im synchronise.

Now each 25 ms the impulse change ( 1 to 0 or 0 to 1 )
I must then Listen if an impulse(1) last more than 25 ms that means
A led must be lit... if i need to tell the system a key has been pressed
i must send a non-impulse(0) to the bus to override Its impulse
to tell him that the user has pressed a key...

but to do this I must control Tx to send data at and extreme precise
time... If it put it into a buffer... I'll miss my delay and the system will be
totally
fuzzed and make beep all the time... even maybe call the police...
So I must not...

Now if you need further information just ask...

BTW: Im working for the security compagny... This is not some kind
of robber plan to disrupt security system... héhé

"Fitzpatrick, Joe" wrote:

> You can bypass the RS232 transceiver with a small Phillips screwdriver and a
> soldering iron...
>
> FWIW, you might get more helpful answers if you would explain what it is you
> are trying to accomplish.  IE, what UART behavior you are trying to
> circumvent and why...
>
> -jjf
>



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