On Thu, 2009-02-26 at 14:29 -0600, Robert wrote:
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breakout box. Lacking one of those, you might find the statserial program to be of some use in figuring out what the control lines are doing. # yum --enablerepo=dag install statserial will install it. It has a short man page. Run with no options except device ( # statserial /dev/ttyS0 ) will cause it to loop, indicating status of all control signals. You can manually tweak any of the pins with direction of "in" with a 9-volt battery or by using a paper-clip
IIRC (very iffy) +/- 12 volts is needed.
jumper from one of the "out" lines. It won't be long before you can identify the port, moving an "unknown" to "found".
There are pins designated to _provide_ the correct voltage full time (on 25 pin units - unsure about 9 pin). The google will get a specification of which they are - I can't remember.
Good luck!
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