I might be wrong, but I don't think this involves a sketch
Because both boards use the ATMega328 chipset, my instructor seems to think the Uno's USB-to-RS-232 converter chip is setting that bit high, but no one knows.
QuoteI might be wrong, but I don't think this involves a sketchGiving the fact that there are literally hundreds (or even thousands) of people using the Uno who do not have this problem there is a very good chance that you are wrong. The most logical and time efficient place to start troubleshooting is with your Sketch. Post your Sketch if you'd like help.A few other things that would be helpful to post...Operating system?Terminal application?
Quote from: nkdy on Apr 29, 2011, 09:26 pmBecause both boards use the ATMega328 chipset, my instructor seems to think the Uno's USB-to-RS-232 converter chip is setting that bit high, but no one knows. You ran the absolutely identical sketch? May we see it?In any case the high-order bit being high sounds to me like the wrong number of bits. Serial has LSB first and MSB last, and the MSB is followed by the stop bit which is a 1. So if you configured the port to use 7 data bits you would get those symptoms.Does the class run to a logic analyzer? You might be able to see what is actually arriving.
We were given predetermined registers to use, and we determined their values via the data sheet. The assignment was written before the Uno was even released.
The program that was tested was not mine; it was my instructors. I'm asking for the differences in HARDWARE, not software. If I thought it was a software problem, I would have said so.
Yes, but when I use serial to talk to my Uno, the 8-bit is not set high. So putting aside whether or not the Duemilanove works, I think it is clutching at staws a bit to assume that there is a serious design issue with the Uno's USB-to-RS-232 converter chip that no-one else in the world has noticed.