Hi Peter,
in fact the circuit plan is only half of the truth because it is a
generic schematic. It only figures out the logical level regardless of
the concrete example. The documentation states the plan to communicate
witha PC-RS232 interface. This doesn't only mean inverting the logical
level of the signal but furthermore converting the low TTL signal -
which might be about 3V (?) high while not transmitting anything, 0V for
the start bit and again 3V (? usually depends on HW) for any 1 set Bit
and Stop Bit - to the logical inverted +-12V signal of a RS232 interface
(self explanatory you cannot expect this level from a max. 3.3V powered
MSP ;°). Possible Hardware you could use is stated in the section
"Demonstration Circuit" in slaa078a.pdf or any other standard RS232
converter (e.g. MAXIM, etc....).
Hope this helps a little bit. Have much fun
Arnd-Hendrik
Peter Mueller wrote:
Hi,
the example in slaa078a (version with 32 kHz) realizes an uart with
2400 Baud 8N1. It uses two hardware inverters in front of rx and tx.
My circuit does not have these converters. Therefore I wanted to
change the program in a way that I do not need them. I played a while
with the CCR unit but unfortunately I could not figure out how to
change the code :-(
Can someone please have a look what must be changed - or is it not
possible with the CCR unit to generate an inverted pattern to the one
generated in the original code?
Thanks a lot for your help!
Regards,
Peter
-------------------------------------------------------
This SF.Net email is sponsored by: YOU BE THE JUDGE. Be one of 170
Project Admins to receive an Apple iPod Mini FREE for your judgement on
who ports your project to Linux PPC the best. Sponsored by IBM.
Deadline: Sept. 13. Go here: http://sf.net/ppc_contest.php
_______________________________________________
Mspgcc-users mailing list
Mspgcc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/mspgcc-users
