SS10 console settings

tony duell ard at
Mon Jun 15 00:24:31 CDT 2015

> The rear DB25 serial connector is an A & B serial port combined.
> Sun had/sold a special Y-splitter cable to use for the combined port.

The RS232 specification allows for 2 serial channels on the DB25 connector. Most
machines only use the primary channel. and Sun were sensible enough to wire their
'2 ports on one connector' so that port A uses the primary channel pins and port B
uses the 'back channel'. This means that if you plug a normal, minimally-wired
serial cable in (say an adapter to a PC DE9 port) you connect to port A. You only
need the splitter cable if you want to use port B


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