Do note that there is a tristate buffer that separates the UART lines between the FTDI and the MSP430. The buffer is tristated when there is no power on the USB 5V line; in order for your solution to work you will have to access the pins on the MSP side of the Tmote Sky, before the signals reach U29.
One other thing to note: if you're using the Boomerang release of Tinyos software from Moteiv and the FramerM component, there is an additional batch of software that will disable UART on disconnection from the USB port. In particular, TX gets turned off immediately after a packet transmission, and FramerM will disable the RX of the UART in software. To understand how that is done, take a look at a file FramerP.nc in /opt/moteiv/tos/platform/tmote/; towards the end of the file you will see event handlers for Detect.connected and Detect.disconnected. Cheers, Rob Robert Szewczyk Moteiv Corporation On 3/22/06, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > Hi, i programmed my TMote to send a byte on usb-serial port when a > Timer signal the "Fired Event". > Then i take the serial output BEFORE of > the FTDI chip, to interface my TMote with > another microcontroller > using RS232 protocol, but when i remove my TMote from Usb port, and i > connect it to my micro, it stop to send data on usb-serial port! so in > my microcontroller receive nothing. > I'm trying this way because using > the expansion serial port, it is shared with radio bus, > and i can lose > very important packets when the bus is assigned to expansion pins. > > Alex > _______________________________________________ > Tinyos-help mailing list > [email protected] > https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help > _______________________________________________ Tinyos-help mailing list [email protected] https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
