Hi,
I had a mica2 conected to a digital oximeter through the UART0. The
baudrate of the conexion is 4800 baudrate and the sensor sends data at a
rate of 1920 bit/s (60 packets per seconds of 4 bytes each one). I merge
sensor data into a TOS_Msg packet, and when it is full I send it over the
radio.
On the other side I have a tipical TOSBase aplication conected to a PC. A
lot of packets seems to be lost, but when you dig in you realise that the
lost are due to bad CRC code. Digging depper you find that the messaje
differs from the original in one "random bit" (statistically taking, some
times you get more than one, but in different bytes). To do this I replace
the oximeter data with a known pattern.
So my first thought was of segmentation fault. I log the SPI SPDR register
into the Flash to then check the corresponding values, and everything
seems OK!.
My only guess now is that the radio and the UART0 share hardware lines. I
dont  know if this may be related to the prog_miso/mosi UART0 conection.
And if this is true I dont know why this doesnt fail in tha case of UART0
comunication with PC and radio transmision. The only difference I see is
the low baudrate of 4800 that may block more time the lines, I dont know??

I am pritty shure it is know sofware problem

thanks in advance, any guess would help

-Bill


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