Hi again,

Please forget this question. (Is that easy to exchange the source of TimerA
and TimerB?)

I have rewritten the MAC layer and AM layer in tinyOS.  All wirings to
TimerB have been removed. Only Timer A provides the clock and timer in my
program. I gave up using printf directly. Instead, a modified node sends
result to a unmodified node by radio. Then the latter print the result.

Thanks.
Wei

On Fri, Jul 13, 2012 at 1:41 PM, Wei Shen <[email protected]> wrote:

> Hi Eric,
>
> Thanks for your answer.
>
> On telosb(MSP430,cc2420) platform, SFD pin of CC2420 is configured to
> TimerB1 capture pin, which is hardware connection! SFD pin can be used to
> capture the moment when a packet arriving. I need a 1MHz source for SFD.
> This is the reason I change the clock source of TimerB1.
> Is that easy to exchange the source of TimerA and TimerB?
>
> Best,
> Wei
>
>
>
>
>
>
> On Mon, Apr 30, 2012 at 1:12 PM, Eric Decker <[email protected]> wrote:
>
>>
>> Before changing something so fundamental, you really need to understand
>> exactly what you are doing.
>>
>> look at examples that are out there on how the low level hardware is
>> configured..  etc.
>>
>> There are also h/w ramifications.
>>
>> On Mon, Apr 30, 2012 at 2:02 AM, Wei Shen <[email protected]> wrote:
>>
>>> Hi all,
>>>
>>> I use tinyos 2.1.1 downloaded from google code. I have changed the
>>> clock source from 32khz to 1MHz of the TimerB of MSP430 in
>>> tos.chips.msp430.timer.
>>
>>
>> Why?
>>
>> 1st TimerB is configured to use the 32KHz clock which is 32768 and driven
>> from a h/w Xtal oscillator.
>>
>> All of the TimerB wiring eventually leads up to providing the main Tmilli
>> source.   The 32KHz clock
>> source is the low power clock and what is used when the mcu goes to sleep.
>>
>> The 32KHz clock and relationship to the main DCO clock (TimerA) is also
>> managed on boot up to sync the
>> DCO clock to something reasonable with respect to the 32KHz clock.
>>  Otherwise the DCO clock can not be
>> exactly set to what is desired.
>>
>> The serial code uses the main DCO clock as its source so if the SMCLK
>> (driven from DCOCLK) is off then
>> the baud rate won't be what it needs to be.
>>
>>
>> Msp430ClockP. In order to match this
>>> modification, I have also changed all counter/timer from wiring to
>>> timerB to timerA. After that, unfortunitely,  the printf does not
>>> work. When i use mincom to print sth, it always garbled characters.
>>>
>>>
>>> I don't know the relationship between /tos/lib/printf  and timerB or
>>> 32khz.  I would really appreciate it if you could help me about this
>>> issue.
>>>
>>
>> Like I said, why?
>>
>>
>>
>>>
>>> Best,
>>> Wei
>>>
>>>>
>>>> --
>>>> Wei Shen
>>>> PhD Student in Mid Sweden University, Sweden
>>>> [email protected]
>>>>
>>>
>>>
>>>
>>> --
>>> Wei Shen
>>> PhD Student in Mid Sweden University, Sweden
>>> [email protected]
>>>
>>> _______________________________________________
>>> Tinyos-help mailing list
>>> [email protected]
>>> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
>>>
>>
>>
>>
>> --
>> Eric B. Decker
>> Senior (over 50 :-) Researcher
>>
>>
>>
>
>
> --
> Wei Shen
> PhD Student in Mid Sweden University, Sweden
> [email protected]
>



-- 
Wei Shen
PhD Student in Mid Sweden University, Sweden
[email protected]
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