[SunRescue] Sun keyboard voltage

[James Lockwood]

On Fri, 28 Jan 2000, Gregory Leblanc wrote:

> Hi guys!  I've been playing with the idea of hooking Sun keyboards to
> PeeCee, and PeeCee keyboard to a Sun.  Right now, I'm all set for
> hooking my Sun keyboard to a PeeCee serial port (I only found drivers
> for Linux).  I'm looking figure out how to go the other way.  I'm
> looking for the signal description of the signal that sun outputs from
> the keyboard connector.  I'd also like to know a little about how the
> TTL RS232 differs from the standard RS232 serial.  Thanks,

TTL RS232 uses TTL voltage levels, +5V and ground.  EIA232 uses a regular
+12/-12V swing.

With regards to hooking PC keyboard up to a Sun, my advice to you is to
find a Sun Interface Converter.  They're only $75 brand new and used are
in the $40-50 range.  They will convert both a keyboard and mouse and
handle remapping of keys on the PC side to simulate Sun L keys.

You could technically hook up a PC keyboard to a Sun serial port as a
synchronous device, but you would have to write your own drivers and you
wouldn't be able to use it at boot time.  Building something to convert
the protocol to attach to the normal Sun keyboard port is fairly involved,
don't even think about it if you don't know about PLD programming. 

If you're still curious, check out the doubleX package.  It has
considerable technical information on how Sun keyboards and mice work.

-James