Hello everybody, 

... I tried searching the web, searching the ACME systems home page, and 
searching through this group - but unfortunatly, I did not find an answer to my 
question. So my last hope is that someone here already faced this problem.

I want to connect a small medical device to the foxboard. This device provides 
a serial connection based on a 5V-TTL-Level. At the moment, it is connected to 
/dev/ttyS0 using the FOX console (http://foxlx.acmesystems.it/?id=106) on 
foxboard-side, and TTL-to-RS232-converter on the medical device side, so that 
the "architecture" is medical device <-> cable to TTL/RS232-converter <-> 
crossed cable to the FOX console <-> foxboard J10. The whole thing works, I can 
communicate and exchange data with the attached device - but of course this is 
not really a "nice" solution because of the two converters involved. That's why 
I would like to directly attach the medical device to the foxboard - according 
to the documentation, the foxboards serial ports on J6 are 5v tolerant, so I 
guess that I at last could try to connect my device to that port without 
causing any damage. Unfortunatly, nothing is said about the port realized at 
J10 - I *guess*, that this also should be 5V tolerant (why should only J6 be?). 
Can perhaps anyone here confirm (or negate) my assumption?

Secondly, what I'm asking myself: it is one thing that this port is 5V tolerant 
- so I may send in signals on the RX line, and the foxboard will know how to 
handle those data. But of course, I will need 5V on the TX line too to ensure 
that the device on the other end of the line can handle the signals send from 
the foxboard. It my assumption correct that the foxboard will send signals at 
3.3V level, and that it is not sure that my device attached at the other end of 
the line will be able to work with those signals? (sorry for this stupid 
question - I'm computer scientist, but this seems more to be a problem for an 
electrical engineer ;-)).

Thanks in advance, and greetings from Dortmund University, Germany
Jan


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