mac serial pinouts

For some odd reason serial ports are always a can of worms. My standard 'algorithm' for hooking up an RS232 device is something like : 1) Read every fine manual associated with the device. 2) Notice that these manuals are written in a confusing way (as an example at least one manual uses 'transmitter protocol' to mean an ETX/ACK handshake and 'receiver protocol' to mean XON/XOFF handshake, no matter if they're applied to the send or receive functions of the device (!)). 3) Configure the device to be at least moderately sane 4) Hook it up to a terminal that uses data leads only and a breakout box. Fiddle with the hardware handshake lines to find out if they behave anything like how the manual describes them. Find out how to make it stop setting and how it tells the other device to stop sending. Some printers use pin 11 (of a DB25) for busy/ready, for example... 5) Wire up a custom adapter to put the signals on sane pins. 6) Try it out 7) Go back to 5 and repeat until it works 8) Label the adapter and hope it stays with the strange device....

There are DEC serial ports that have no hardware handshaking at all. There are HP machines were the hardware handshake is sufficiently strange that I'd love to know what the designer was thinking about. There are printers with the ready signal on a strange pin. And so on. No 2 manufacturers do it the same way. FWIW it _is_ a DE9. This sounds like it's designed to connect to some special Apple device (most async devices don't use external clocking, for example) rather than a normal device like a printer or a modem.

-tony