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Re: twiddler size

 From: "Legacy 'Xunker'" <>
>Looks nice.  It looks like the only line connected are RX, TX, GND and
>RTS/CTS.  I've only have a little electronics training, and it confuses
>me how RTS and CTS can work on the same line..  Also, IMS, isn't
>RTS/CTS for hardware flow control anyway?  1200 can use Xon/Xoff, so
>you've got it down to 3 pins.  I'm asking this because my HP95LX serial
>port only has 3 "real" pins: RX,TX and GND/DTR.

The way it works is that by default, rx and tx are "shorted" together,
so that they are at the same level which to the computer appears as "no
data present"

You then twiddle the transistor on and off to create your bit
waveforms.

the rts/cts is used for power, and you can substitute DTR, that'll work
just fine.  However, without a source of power, you'll have to add two
AA batteries to provide the 3v you need.  AAA batteries might even
work.  I don't know about the power drain.

You might be able to make the device auto-power on when the rx line
goes low (i.e. when the HP95lx serial port is active) so you can
conserve batteries that way.

   - Kevin

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