In comp.arch.embedded,
Frnak McKenney <frnak@far.from.the.madding.crowd.com> wrote:
> On Fri, 05 Dec 2008 00:04:06 +0100, Stef <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote:
>> In comp.arch.embedded, steve <bungalow_steve@yahoo.com> wrote:

>> Shame actually, since it would be an ideal fit for what we are starting
>> now. Currently investigating msp430+cc1050 as the cc1050's internal 8051
>> is a bit power hungry if you want any osc running in power down.
>
> Have you also considered the MSP430+CC2500 combination? TI offers
> an inexpensive development kit ($50US?) with a pair of boards, one
> powered from a 2xAA battery pack and the other from a USB
> "programming dongle".
>
> If you're not already aware of the kit, look for TI document slau227c,
> "ez430-RF2500T Development Tool" for an overview and circuit diagrams.

The cc2500 is 2.4GHz, we need 868MHz for our data transfer. At least that
is the current selection, but things may change later. :-)

I was just searching for the required tools (compiler, devboards etc.) and
found this page (well just click the 'tools' link on msp430 page ;-) ):
http://focus.ti.com/mcu/docs/mcuprodtoolsw.tsp?sectionId=95&tabId=1203&familyId=342&toolTypeId=1

The kit you mention is on there as well as many others, all very
affordable, even the IDE/compiler kit.

-- 
Stef    (remove caps, dashes and .invalid from e-mail address to reply by mail)

Kirk to Enterprise -- beam down yeoman Rand and a six-pack.

On Fri, 05 Dec 2008 00:04:06 +0100, Stef <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote:
> In comp.arch.embedded, steve <bungalow_steve@yahoo.com> wrote:
>> TI has a neat wireless MSP430, called the CC430 you may be interested
>> in, see
>> http://www.ti.com/corp/docs/landing/cc430/index.htm
> 
> "Has" may be a bit optimistic if you want to start development now:
> 
>   "The first CC430 samples will be available in limited quantities in
>    1Q09 with mass-market sampling and further device introductions
>    scheduled for later in the year"
> 
> Shame actually, since it would be an ideal fit for what we are starting
> now. Currently investigating msp430+cc1050 as the cc1050's internal 8051
> is a bit power hungry if you want any osc running in power down.

Stef,

Have you also considered the MSP430+CC2500 combination? TI offers
an inexpensive development kit ($50US?) with a pair of boards, one
powered from a 2xAA battery pack and the other from a USB
"programming dongle".

If you're not already aware of the kit, look for TI document slau227c,
"ez430-RF2500T Development Tool" for an overview and circuit diagrams.


Frank McKenney
--
    I do not deny that laws are important, but...the passage of new
    laws has continually served as a substitute for thought.
                             -- Aldo Leopold
--
Frank McKenney, McKenney Associates
Richmond, Virginia / (804) 320-4887
Munged E-mail: frank uscore mckenney ayut mined spring dawt cahm (y'all)

In comp.arch.embedded,
larwe <zwsdotcom@gmail.com> wrote:
>
>> Shame actually, since it would be an ideal fit for what we are starting
>> now. Currently investigating msp430+cc1050 as the cc1050's internal
>
> Why cc1050 and not cc1101?

Because the cc1101 is a tranceiver and cc1050 is a transmitter, we
transmit only. Receiver side will be a completely different device
which will not be that power critical, so more choices for RF and CPU.

-- 
Stef    (remove caps, dashes and .invalid from e-mail address to reply by mail)

I found Rome a city of bricks and left it a city of marble.
		-- Augustus Caesar

> Shame actually, since it would be an ideal fit for what we are starting
> now. Currently investigating msp430+cc1050 as the cc1050's internal

Why cc1050 and not cc1101?

In comp.arch.embedded,
steve <bungalow_steve@yahoo.com> wrote:
>
> TI has a neat wireless MSP430, called the CC430 you may be interested
> in, see
>
> http://www.ti.com/corp/docs/landing/cc430/index.htm

"Has" may be a bit optimistic if you want to start development now:

  "The first CC430 samples will be available in limited quantities in
   1Q09 with mass-market sampling and further device introductions
   scheduled for later in the year"

Shame actually, since it would be an ideal fit for what we are starting
now. Currently investigating msp430+cc1050 as the cc1050's internal 8051
is a bit power hungry if you want any osc running in power down.


-- 
Stef    (remove caps, dashes and .invalid from e-mail address to reply by mail)

Did it ever occur to you that fat chance and slim chance mean the same thing?

Or that we drive on parkways and park on driveways?

On Dec 4, 9:08=A0am, "cellmania" <pulkitpandey1...@gmail.com> wrote:
> i am working on a project on wireless sensors....i need a processor where
> the clock frequency can be varied during RUN-TIME so as use in low-power
> applications....but it must not be as low as is the case in the sleep
> mode.
>
> i found that the option of variable frequency is not available in avr
> controllers on which i have worked on till now...i was thinking about
> msp430 series but i cannot find a relation between clock frequency and
> power mode in this processor....
>
> can anyone help me with more info about power control in msp....

Variable frequency is allowed in AVR's and MSP430 down to very low
frequecies with near linear power reduction.  Other processors you
can't do this (ARM Cortex for instance).


TI has a neat wireless MSP430, called the CC430 you may be interested
in, see

http://www.ti.com/corp/docs/landing/cc430/index.htm

cellmania wrote:
> i am working on a project on wireless sensors....i need a processor where
> the clock frequency can be varied during RUN-TIME so as use in low-power
> applications....but it must not be as low as is the case in the sleep
> mode.
> 
> i found that the option of variable frequency is not available in avr
> controllers on which i have worked on till now...i was thinking about
> msp430 series but i cannot find a relation between clock frequency and
> power mode in this processor....
> 
> can anyone help me with more info about power control in msp....
> 
> 

The DCO (resistance controlled  oscillator) can be varied dynamically, 
and its basic frequency changed by switching between the internal 
resistance and an external one. The crystal clock can be turned off, and 
some variants have two crystal oscillators, so one can be a high 
frequency clock while the other runs from a 32kHz crystal. In addition, 
you can slow down (via 1/2/4/8 selectable dividers) or turn off clocks 
to the peripherals.

There are also 5 low power modes:

LPM0 - The CPU is disabled.
LPM1 - The loop control for the fast clock (MCLK) is also disabled.
LPM2 - The fast clock (MCLK) is also disabled.
LPM3 - The DCO oscillator and its DC generator are also disabled.
LPM4 - The crystal oscillator is also disabled.

with decreasing power, but increased wakeup time, as the number rises.

(partly from http://mspgcc.sourceforge.net/manual/x641.html)

It's all in the appnotes on the TI website, though rather distributed 
all over the shop.

JS

In comp.arch.embedded,
cellmania <pulkitpandey1988@gmail.com> wrote:
> i am working on a project on wireless sensors....i need a processor where
> the clock frequency can be varied during RUN-TIME so as use in low-power
> applications....but it must not be as low as is the case in the sleep
> mode.
>
> i found that the option of variable frequency is not available in avr
> controllers on which i have worked on till now...i was thinking about
> msp430 series but i cannot find a relation between clock frequency and
> power mode in this processor....
>
> can anyone help me with more info about power control in msp....

Just reading up on them myself. :-)
The information on power consumption and modes is split between the
individual datasheets and the User's Guide.
I don't know which derivative you are researching, but the user's guide
for the MSP430x1xxx (slua049f.pdf) has a nice picture of the clockmodule.
As far as I understand it, you can only control the frequency of the DCO.
But you can switch between different clock sources. There is also a
description on which clocks are enabled during which power mode.


-- 
Stef    (remove caps, dashes and .invalid from e-mail address to reply by mail)

The trouble with heart disease is that the first symptom is often hard to
deal with: death.
		-- Michael Phelps

cellmania schrieb:
> i am working on a project on wireless sensors....i need a processor where
> the clock frequency can be varied during RUN-TIME so as use in low-power
> applications....but it must not be as low as is the case in the sleep
> mode.
> 
> i found that the option of variable frequency is not available in avr
> controllers on which i have worked on till now...i was thinking about
> msp430 series but i cannot find a relation between clock frequency and
> power mode in this processor....

In the datasheet for MSP430F135 processor, page 25, chapter "electrical 
characteristics/supply current":
Current consumption of active mode versus system frequency
I(AM) = I(AM)[1 MHz] x f(system)[MHz]
I(AM)[1 MHz] is about 300 uA.
So it's pretty linear and in the ballpark for other types of mcu.

The trick of MSP430 is a fast wakeup from sleep and easy change of 
frequency. If you can live with the internal oscillator (DCO), you can 
set its frequency according to slau049.pdf, chapter "4: basic clock 
module" by changing DCOCTL. There are three clock lines: MCLK (clock for 
processor core), SMCLK (clock for peripherals) and ACLK (second clock 
for peripherals). Every clock line has a prescaler (DIVM,DIVS and DIVA) 
which divides DCO clock (/1, /2, /4 or /8).
In addition to that, you can stop every clock by setting some bits in 
the status register. In this case the peripherals and the core are fully 
static and an interrupt restarts the core clock.

cheers
Gunther

On Thu, 04 Dec 2008 08:08:02 -0600
"cellmania" <pulkitpandey1988@gmail.com> wrote:

> i am working on a project on wireless sensors....i need a processor
> where the clock frequency can be varied during RUN-TIME so as use in
> low-power applications....but it must not be as low as is the case in
> the sleep mode.
> 
> i found that the option of variable frequency is not available in avr
> controllers on which i have worked on till now...i was thinking about
> msp430 series but i cannot find a relation between clock frequency and
> power mode in this processor....
> 
> can anyone help me with more info about power control in msp....
> 
> 

Do you really need to vary the master clock frequency, or can you just
go into low-power sleep mode and then wake back up on either a periodic
or externally generated interrupt?  That's the strategy that seemed to
be pretty much par for the MSP430 course, as I recall.  

-- 
Rob Gaddi, Highland Technology
Email address is currently out of order