Chris,<br><br>I understand you had posted to the incorrect mailing list, but your question intrigued me. The first link in the question does not work, is that the correct link?<br><br>And for a UART, you definitely need level shifting (ie. like a MAX232, etc.) if connecting to +/-12v serial line, at the very least to avoid damaging the UART by overvoltage. In some cases, it is possible to do w/o the level shifting, due to the requirements in the RS-232 specs for the RX line of most UARTs, which are required to distinguish signals as low as +/-3v. Results are varied, as not every manu. follows the specs. verbatim.<br>
<br>-Kyle Bassett<br><br><br><div class="gmail_quote">On Feb 3, 2008 6:11 PM, Chris <<a href="mailto:lists@proquariat.de">lists@proquariat.de</a>> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Hi,<br><br>I tried this: <a href="http://owfs.sourceforge.net/WRT54G.html" target="_blank">http://owfs.sourceforge.net/WRT54G.html</a> and it doesn't<br>work for me.<br><br>It looks really weird how the author connected the DS2480B, which runs<br>
at 5V directly to the UART, which provides only 3.3V. I think this would<br>need some level-shifting.<br>The datasheet also says the POL-Pin (Pin6) has to be tied to +5V if<br>directly connected to the UART.<br><br>I made a small schematic with some resistors as level shifters:<br>
<a href="http://img228.imageshack.us/img228/4611/ds2480bwrtmp0.png" target="_blank">http://img228.imageshack.us/img228/4611/ds2480bwrtmp0.png</a> but I don't<br>think I like it. It's said that doing level shifting is very power hungry.<br>
<br>Any better ideas?<br><br>-Chris<br><br>_______________________________________________<br>OpenMoko community mailing list<br><a href="mailto:community@lists.openmoko.org">community@lists.openmoko.org</a><br><a href="http://lists.openmoko.org/mailman/listinfo/community" target="_blank">http://lists.openmoko.org/mailman/listinfo/community</a><br>
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