Re: Pin-out wanted for Apple //e workstation card serial ports

[dempson@actrix.gen.nz (David Empson)]

David Wilson <david@uow.edu.au> wrote:

> If anyone can give me the pin-outs for the two serial cables (I assume they
> are both the same) for an Apple //e workstation card I would be grateful.

The same as the IIgs serial port:

 8 7 6
5  4 3
  2 1

1  Handshake Out
2  Handshake In
3  TxD-
4  Signal ground
5  TxD+
6  RxD-
7  Unused
8  RxD+

For LocalTalk, the RxD+/- and TxD+/- pins are used, together with signal
ground.  The drop box mixes the Tx and Rx signals together via a
transformer.  Transmit enable is controlled internally - the TxD+ and
TxD- signals are set to high impedance (or possibly just grounded) while
not transmitting, or are at +/-5V (ish) when transmit is enabled.

For a serial printer, HShkOut and HShkIn are used for flow control, and
TxD- and RxD- are used for data.  TxD+ should not be connected, and RxD+
should be connected to ground.

(An ImageWriter II is also RS-422, so it can have the positive and
negative data signals hooked up.)

> I intend patching the EPROM to at a minimum add support for the ProDOS
> hidden bit.

Good luck!  At least the card's CPU is a 65(C)02, which makes the
disassembly more straightforward.

-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand