50g serial port tech. - Help.

[Vtile]

Hello, I have seen somewhere a techical specification for 50g serial port, something like serial communication manual or something on those lines, now I just can't find it on hpcalc.org. My memory says it did also had some form of HW specs for the port at some level.

I have basic knowledge of the port at the back of my head, but would be nice to read the manual/writing anyway.

I'm sure I have seen it there before ...somewhere.

.. Another question.. Can anyone see any pitfalls in HW hack that turns the (supposed) always on Vcc (directly from batteries) line off, while calculator is turned off ??? IIRC the SD card Vcc goes down with the calculator so basicly one N-channel 3.3V logiclevel MOSFET should do the trick ... Free space inside of the calculator is not a problem at all.