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Unread 24-08-2008, 16:17
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Engineer at Medrobotics
AKA: Dr. Joe
FRC #0088 (TJ2)
Team Role: Engineer
 
Join Date: May 2001
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Re: Serial communication help

Quote:
Originally Posted by tdlrali View Post
There's a second serial port on the RC, labeled TTL. That second programming port works just like the 1st. If the sound chip needs RS232 levels, you can use the little converter board that came with the cmucams.


What prevents you from connecting the laptop directly to the sound chip?
If you don't have the CMUCAM level shifter, it is almost trivial to build one with a MAX232 or MAX233 chip -- add a few caps, a few wires and some solder and you're in business.

Alternatively, you may be able to track down the level shifter on the sound board you are using and tap into the board where the serial data is TTL voltages again -- this will take more courage on your part, but you seem like a bold kind of guy, so I think you could handle it (don't forget to cut the trace from the output of the level shifter so that the IFI output and the level shifter are not fighting to control the same line).

Good luck,

Joe J.
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