thanks roman, the problem was with the voltage levels. Since the telosb works on a Vcc=3V and the RS232 specifies a logic level of 5V it needs a level shifter to convert the voltage levels from telosb to RS232. I used a switching transistor to convert the voltage levels.
Vaibhav ----- Original Message ---- From: Roman Lim <[EMAIL PROTECTED]> To: Vaibhav Nagarnaik <[EMAIL PROTECTED]> Cc: [email protected] Sent: Monday, October 8, 2007 12:41:00 AM Subject: Re: [Tinyos-help] Problem with communicating with PC using UART0 on telos ver.B for tinyos 2.x do you use a levelshifter on your crossover cable? the voltage level for pc communication is +/-5v if i remember it correctly. in http://tinyos.cvs.sourceforge.net/tinyos/tinyos-2.x-contrib/ethz/snpk/tos/lib/dsn/ you can find a working tos2 implementation of a uart0 communication with tmote. roman Vaibhav Nagarnaik wrote: > > > Hi All, > > Any ideas yet why I can't communicate using UART0 from telosb? > > I have confirmed that the cross-over serial cable is good for communication > and that there is no other problem. Is it something to do with using some > kind of chip select for the multiplexed bus on UART0 and CC2420? > > All I have got from the archives is a solution for tinyos 1.x to use > BusArbitration module. But I am using 2.x and I think using Resource > interface provided by Msp430Usart0C should be enough. Is this correct? > > Any other people having similar troubles? > > > > Vaibhav > > ----- Original Message ---- > From: Kevin Klues <[EMAIL PROTECTED]> > To: Vaibhav Nagarnaik <[EMAIL PROTECTED]> > Cc: [email protected] > Sent: Thursday, October 4, 2007 3:30:15 PM > Subject: Re: [Tinyos-help] Problem with communicating with PC using UART0 on telos ver.B for tinyos 2.x > > I'm actually surprised you see anything at all...... > You can't use USART0 to communicate with the PC because it isn't > physically connected to the serial port on the telos -- there are no > wires connecting USART0 to the USB controller to exchange data with > the PC. > > USART0 is attached to the radio, the flash, and the external connector > pins, while USART1 is attached to the serial port. > > As a side note...... > You should consider using something other than while() loops in the > way that you do if you actually start implementing something > substantial in TinyOS. Because of the concurrency model that TinyOS > uses, using while() loops to wait on a flag without really knowing > what you are doing could cause your program to lock up and never break > out of the loop. Using a split-phase operation is preferred. Just a > word of caution for anyone considering doing this. > > Kevin > > On 10/4/07, Vaibhav Nagarnaik <[EMAIL PROTECTED]> wrote: >> Hi All, >> >> I am trying to use tinyos 2.x with telosb to communicate with PC using UART0. >> >> I have tried different components Msp430Usart0C and Msp430Uart0C but I don't receive the same character sent from PC. >> >> For example if I send 'a' from PC, I get '0x58 0x08 0x01 0x00' ie four characters on the PC. Even when the code explicitly sends 1 byte. >> >> I have set baud rate on the PC to 57600. If I run the same code using Msp430Usart1C component, there is no problem. >> >> Can anyone please point me to the problem in this code? >> >> Following is the sample code I am trying to run. >> >> configuration TestSerialAppC {} >> implementation { >> components TestSerialC as App, MainC, LedsC; >> >> components new Msp430Usart0C() as usart0; >> >> App.Boot -> MainC; >> App.Leds -> LedsC; >> >> App.usart -> usart0; >> App.UsartResource -> usart0; >> } >> >> module TestSerialC { >> uses { >> interface HplMsp430Usart as usart; >> interface Boot; >> interface Resource as UsartResource; >> interface Leds; >> } >> } >> >> implementation { >> event void Boot.booted() { >> while (call UsartResource.request() != SUCCESS); >> } >> event void UsartResource.granted() { >> uint8_t data; >> call usart.setModeUart(&msp430_uart_default_config); >> call usart.enableUart(); >> >> while (1) { >> call Leds.led1On(); >> while (! call usart.isRxIntrPending()); >> call Leds.led1Off(); >> >> data = call usart.rx(); >> call usart.clrRxIntr(); >> >> call Leds.led0On(); >> call usart.tx(data); >> >> while (! call usart.isTxEmpty()); >> if (call usart.isTxIntrPending()) { >> call usart.clrTxIntr(); >> } >> call Leds.led0Off(); >> } >> } >> } >> >> >> >> Any help is appreciated. >> >> Vaibhav >> __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
