[Tinyos-help] Is transmitted packet size fixed or variable?

2008-03-30 Thread David
Hi list. I've taken a look at tep111 and tep126, but there's something which isn't clear to me from the teps. Are the packets transmitted over radio a fixed length or variable (based on requested payload length)? eg, if you leave TOSH_DATA_LENGTH at 28, but send a payload of 2 bytes, will the ot

Re: [Tinyos-help] Is transmitted packet size fixed or variable?

2008-03-31 Thread Kevin Klues
If you call send() with a length of 2 bytes, only two bytes will be transmitted over the air. The TOSH_DATA_LENGTH paramter basically determines the maximum size of the payload you could ever send and receive. Essentially, it is used to define the size of the data portion of the message_t struct

Re: [Tinyos-help] Is transmitted packet size fixed or variable?

2008-03-31 Thread SANG Junjun
I think it depends on the radio. Because some radio can only send/recv a fixed size of packet, for example nRF905. On Mon, Mar 31, 2008 at 3:06 PM, Kevin Klues <[EMAIL PROTECTED]> wrote: > If you call send() with a length of 2 bytes, only two bytes will be > transmitted over the air. The TOSH_D

Re: [Tinyos-help] Is transmitted packet size fixed or variable?

2008-03-31 Thread David
Do you know if this applies to the cc2400, or where I can look this up? Thanks, David. On Mon, Mar 31, 2008 at 10:54 AM, SANG Junjun <[EMAIL PROTECTED]> wrote: > I think it depends on the radio. > Because some radio can only send/recv a fixed size of packet, for example > nRF905. > > > On Mon, M

Re: [Tinyos-help] Is transmitted packet size fixed or variable?

2008-03-31 Thread renjie huang
You meant cc2420? In fact , you can take a look at the code of CC2420Radio module. It transmits how many bytes your ask it to transmit. On 3/31/08, David <[EMAIL PROTECTED]> wrote: > > Do you know if this applies to the cc2400, or where I can look this up? > > Thanks, > > David. > > On Mon, Mar 31

Re: [Tinyos-help] Is transmitted packet size fixed or variable?

2008-03-31 Thread Kevin Klues
CC2400 data sheet and info http://focus.ti.com/docs/prod/folders/print/cc2400.html Kevin On Mon, Mar 31, 2008 at 2:03 AM, David <[EMAIL PROTECTED]> wrote: > Do you know if this applies to the cc2400, or where I can look this up? > > Thanks, > > David. > > > > On Mon, Mar 31, 2008 at 10:54 AM,