Mike,
yes, the MSP430 core on that board could not running at 12 MHz but they are
beyond the specs anyway! The fact they stated the limit of 8MHz at 2.8V
(SLAS368C) do not mean they warrant you that the clock works at 12 MHz at
3,6 V.
By the way I too recall of 10 MHz max for the external clock but it seems
that in the recent datasheets or maybe only in some families (like in the
Kris' story) they switched to a more conservative 8 MHz.
I'm still on the conviction they taken a lot of margin on the recommended
operating conditions because they not test them.
Cheers,
Bruno
-----Messaggio Originale-----
Da: "Mike"
A:
Data invio: mercoled21 febbraio 2007 6.20
Oggetto: [msp430] Re: Running at 3.3V @8 MHz
Hi Bruno,
The processor isn't necessarily running at 12 MHz... The clock and
peripherals can run faster than the core. The specs say 10 MHz at 3V,
and the designer may have extrapolated for 12 MHz at 3.6V.
Most likely, the designer used the 12 MHz clock from the TUSB3410 to
save the cost of another crystal, and divided the clock before it
went to the core and/or peripherals.
Mike.
Kaelin Consulting
m...@kaelinconsulting.com
--- In m..., "Bruno Galli" wrote:
>
> Hi folks,
>
> not too much surprisingly even TI uses its chip beyond clock
specifications.
> If you look at the eZ430U development board
you'll find an
MSP430F16x
> running at *12 MHz* at 3.6V! (It uses the 12 MHz
because of the USB
chip.)
>
> I guess they had been very conservative to save on test budget.
>
> By the way, if you want to be strictly on specs keep in mind that
you have
> to run above 3.6V to have enough room for regulator
IC overall
tolerance.
>
> Cheers,
> Bruno
>
> -----Messaggio Originale-----
> Da: "John C. Westmoreland, P.E."
> A:
> Data invio: venerd16 febbraio 2007 20.12
> Oggetto: Re: [msp430] Running at 3.3V @8 MHz
> | The design team on a project I worked on a couple of years ago
went round
> and round on this. Talked to TI several times, etc.
This could be
part
> specific maybe; we were using the '1611 - since
it had to pass FDA -
it was
> determined that we had to have Vcc be 3.6V.
> |
> | Sent via BlackBerry from T-Mobile
> |
> | -----Original Message-----
> | From: Hugh Molesworth
> | Date: Fri, 16 Feb 2007 10:45:49
> | To:m...
> | Subject: Re: [msp430] Running at 3.3V @8 MHz
> |
> | We asked TI about this and they stated that the frequency
restriction only
> | applies to the cpu core and not the crystal and
associated
divider
> circuits.
> | Therefore use of 8MHz is within spec provided that the core and
> peripherals are
> | clocked - as suggested - at 4MHz.
> |
> | Hugh
> |
> | --- "John C. Westmoreland, P.E."
> gineering.com> wrote:
> |
> | > The graph on the '1611 is clear regarding running at 8MHz - the
supply
> | > voltage needs to
> | > be 3.6VDC. If you want to run out of spec - that's up to you -
but if
> your
> | > project requires
> | > running in spec - then your Vcc needs to be 3.6VDC.
> | >
> | > Having said that - when hunting for speed paths - I've run
the '1611
> (rev. B)
> | > at 10MHz and 12MHz, but
> | > my Vcc was always 3.6VDC. The part will work with different
> | > voltages/frequencies - but it all depends
> | > if you want to be in spec - or if the project specifications
require (to
> be
> | > in spec...).
> | >
> | > Dividing MCLK by 2 as you have asked will work - that means the
core
> will be
> | > clocked at 4MHz - but
> | > there's still the question of the divider circuit and the I/F
circuitry
> to
> | > the oscillator running at 8MHz - which
> | > is still out of spec.
> | >
> | > Regards,
> | > John W.
> | >
> | >
> | > ----- Original Message -----
> | > From: mago Umandam
> | > To: msp430@yahoogroups.: com
> | > Sent: Thursday, February 15, 2007 4:43 PM
> | > Subject: Re: [msp430] Running at 3.3V @8 MHz
> | >
> | >
> | > Hi,
> | >
> | > I am using 8MHz in 3.3V VCC and so far so good. I have not read
from
> | > datasheet that 8 MHz requires 3.6V VCC. Datasheet
page 24 says
that 8
> MHz can
> | > be run at VCC greater than 2.8 Volts.
> | >
> | > mago
> | >
> | >
> | > markcrowptm > wrote:
> | > On my project, VCC can run from 1.8V to 3.3V and my oscillator
is 8
> | > MHz. Unfortunately I'm not in a position
make any hardware
changes.
> | > The data sheet for the MSP430F1611 seems to
indicate that the
micro can
> | > only run at 8 MHz if VCC is 3.6V. It indicates I
can run with
my VCC
> | > issues at 4 MHz. Can I then simply program the
clock control
register
> | > BCSCTL2 to divide MCLK by 2 and solve the
problem?
> | >
> | > Thanks in advance.
> | >
> | > ---------------------------------
> | > Need Mail bonding?
> | > Go to the Yahoo! Mail Q&A for great tips from Yahoo! Answers
users.
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | > >
> egroups.com
> | >
> | >
> | > Yahoo! Groups Links
> | >
> | >
> | >
> | >
> |
> |
> |
> |
> |
> |
> |
> | Yahoo! Groups Links
> |
> |
> |
>
Yahoo! Groups Links
Running at 3.3V @8 MHz
Started by ●February 15, 2007
Reply by ●February 21, 20072007-02-21
Reply by ●February 21, 20072007-02-21
Hi Mike,
> The processor isn't necessarily running at 12 MHz... The clock and
> peripherals can run faster than the core.
It's actually the other way around. The core can run faster, but it's the peripherals that are the
problem speed wise.
Best Regards,
Kris
-----Original Message-----
From: m... [mailto:m...] On Behalf Of Mike
Sent: Wednesday, 21 February 2007 4:20 PM
To: m...
Subject: [msp430] Re: Running at 3.3V @8 MHz
Hi Bruno,
The processor isn't necessarily running at 12 MHz... The clock and
peripherals can run faster than the core. The specs say 10 MHz at 3V,
and the designer may have extrapolated for 12 MHz at 3.6V.
Most likely, the designer used the 12 MHz clock from the TUSB3410 to
save the cost of another crystal, and divided the clock before it
went to the core and/or peripherals.
Mike.
Kaelin Consulting
m...@kaelinconsulting.com
--- In m..., "Bruno Galli" wrote:
>
> Hi folks,
>
> not too much surprisingly even TI uses its chip beyond clock
specifications.
> If you look at the eZ430U development board you'll find an
MSP430F16x
> running at *12 MHz* at 3.6V! (It uses the 12 MHz because of the USB
chip.)
>
> I guess they had been very conservative to save on test budget.
>
> By the way, if you want to be strictly on specs keep in mind that
you have
> to run above 3.6V to have enough room for regulator IC overall
tolerance.
>
> Cheers,
> Bruno
>
> -----Messaggio Originale-----
> Da: "John C. Westmoreland, P.E."
> A:
> Data invio: venerd16 febbraio 2007 20.12
> Oggetto: Re: [msp430] Running at 3.3V @8 MHz
> | The design team on a project I worked on a couple of years ago
went round
> and round on this. Talked to TI several times, etc. This could be
part
> specific maybe; we were using the '1611 - since it had to pass FDA -
it was
> determined that we had to have Vcc be 3.6V.
> |
> | Sent via BlackBerry from T-Mobile
> |
> | -----Original Message-----
> | From: Hugh Molesworth
> | Date: Fri, 16 Feb 2007 10:45:49
> | To:m...
> | Subject: Re: [msp430] Running at 3.3V @8 MHz
> |
> | We asked TI about this and they stated that the frequency
restriction only
> | applies to the cpu core and not the crystal and associated
divider
> circuits.
> | Therefore use of 8MHz is within spec provided that the core and
> peripherals are
> | clocked - as suggested - at 4MHz.
> |
> | Hugh
> |
> | --- "John C. Westmoreland, P.E." > gineering.com> wrote:
> |
> | > The graph on the '1611 is clear regarding running at 8MHz - the
supply
> | > voltage needs to
> | > be 3.6VDC. If you want to run out of spec - that's up to you -
but if
> your
> | > project requires
> | > running in spec - then your Vcc needs to be 3.6VDC.
> | >
> | > Having said that - when hunting for speed paths - I've run
the '1611
> (rev. B)
> | > at 10MHz and 12MHz, but
> | > my Vcc was always 3.6VDC. The part will work with different
> | > voltages/frequencies - but it all depends
> | > if you want to be in spec - or if the project specifications
require (to
> be
> | > in spec...).
> | >
> | > Dividing MCLK by 2 as you have asked will work - that means the
core
> will be
> | > clocked at 4MHz - but
> | > there's still the question of the divider circuit and the I/F
circuitry
> to
> | > the oscillator running at 8MHz - which
> | > is still out of spec.
> | >
> | > Regards,
> | > John W.
> | >
> | >
> | > ----- Original Message -----
> | > From: mago Umandam
> | > To: msp430@yahoogroups.: com
> | > Sent: Thursday, February 15, 2007 4:43 PM
> | > Subject: Re: [msp430] Running at 3.3V @8 MHz
> | >
> | >
> | > Hi,
> | >
> | > I am using 8MHz in 3.3V VCC and so far so good. I have not read
from
> | > datasheet that 8 MHz requires 3.6V VCC. Datasheet page 24 says
that 8
> MHz can
> | > be run at VCC greater than 2.8 Volts.
> | >
> | > mago
> | >
> | >
> | > markcrowptm > wrote:
> | > On my project, VCC can run from 1.8V to 3.3V and my oscillator
is 8
> | > MHz. Unfortunately I'm not in a position make any hardware
changes.
> | > The data sheet for the MSP430F1611 seems to indicate that the
micro can
> | > only run at 8 MHz if VCC is 3.6V. It indicates I can run with
my VCC
> | > issues at 4 MHz. Can I then simply program the clock control
register
> | > BCSCTL2 to divide MCLK by 2 and solve the problem?
> | >
> | > Thanks in advance.
> | >
> | > ---------------------------------
> | > Need Mail bonding?
> | > Go to the Yahoo! Mail Q&A for great tips from Yahoo! Answers
users.
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | > >
> egroups.com
> | >
> | >
> | > Yahoo! Groups Links
> | >
> | >
> | >
> | >
> |
> |
> |
> |
> |
> |
> |
> | Yahoo! Groups Links
> |
> |
> |
>
Yahoo! Groups Links
> The processor isn't necessarily running at 12 MHz... The clock and
> peripherals can run faster than the core.
It's actually the other way around. The core can run faster, but it's the peripherals that are the
problem speed wise.
Best Regards,
Kris
-----Original Message-----
From: m... [mailto:m...] On Behalf Of Mike
Sent: Wednesday, 21 February 2007 4:20 PM
To: m...
Subject: [msp430] Re: Running at 3.3V @8 MHz
Hi Bruno,
The processor isn't necessarily running at 12 MHz... The clock and
peripherals can run faster than the core. The specs say 10 MHz at 3V,
and the designer may have extrapolated for 12 MHz at 3.6V.
Most likely, the designer used the 12 MHz clock from the TUSB3410 to
save the cost of another crystal, and divided the clock before it
went to the core and/or peripherals.
Mike.
Kaelin Consulting
m...@kaelinconsulting.com
--- In m..., "Bruno Galli" wrote:
>
> Hi folks,
>
> not too much surprisingly even TI uses its chip beyond clock
specifications.
> If you look at the eZ430U development board you'll find an
MSP430F16x
> running at *12 MHz* at 3.6V! (It uses the 12 MHz because of the USB
chip.)
>
> I guess they had been very conservative to save on test budget.
>
> By the way, if you want to be strictly on specs keep in mind that
you have
> to run above 3.6V to have enough room for regulator IC overall
tolerance.
>
> Cheers,
> Bruno
>
> -----Messaggio Originale-----
> Da: "John C. Westmoreland, P.E."
> A:
> Data invio: venerd16 febbraio 2007 20.12
> Oggetto: Re: [msp430] Running at 3.3V @8 MHz
> | The design team on a project I worked on a couple of years ago
went round
> and round on this. Talked to TI several times, etc. This could be
part
> specific maybe; we were using the '1611 - since it had to pass FDA -
it was
> determined that we had to have Vcc be 3.6V.
> |
> | Sent via BlackBerry from T-Mobile
> |
> | -----Original Message-----
> | From: Hugh Molesworth
> | Date: Fri, 16 Feb 2007 10:45:49
> | To:m...
> | Subject: Re: [msp430] Running at 3.3V @8 MHz
> |
> | We asked TI about this and they stated that the frequency
restriction only
> | applies to the cpu core and not the crystal and associated
divider
> circuits.
> | Therefore use of 8MHz is within spec provided that the core and
> peripherals are
> | clocked - as suggested - at 4MHz.
> |
> | Hugh
> |
> | --- "John C. Westmoreland, P.E." > gineering.com> wrote:
> |
> | > The graph on the '1611 is clear regarding running at 8MHz - the
supply
> | > voltage needs to
> | > be 3.6VDC. If you want to run out of spec - that's up to you -
but if
> your
> | > project requires
> | > running in spec - then your Vcc needs to be 3.6VDC.
> | >
> | > Having said that - when hunting for speed paths - I've run
the '1611
> (rev. B)
> | > at 10MHz and 12MHz, but
> | > my Vcc was always 3.6VDC. The part will work with different
> | > voltages/frequencies - but it all depends
> | > if you want to be in spec - or if the project specifications
require (to
> be
> | > in spec...).
> | >
> | > Dividing MCLK by 2 as you have asked will work - that means the
core
> will be
> | > clocked at 4MHz - but
> | > there's still the question of the divider circuit and the I/F
circuitry
> to
> | > the oscillator running at 8MHz - which
> | > is still out of spec.
> | >
> | > Regards,
> | > John W.
> | >
> | >
> | > ----- Original Message -----
> | > From: mago Umandam
> | > To: msp430@yahoogroups.: com
> | > Sent: Thursday, February 15, 2007 4:43 PM
> | > Subject: Re: [msp430] Running at 3.3V @8 MHz
> | >
> | >
> | > Hi,
> | >
> | > I am using 8MHz in 3.3V VCC and so far so good. I have not read
from
> | > datasheet that 8 MHz requires 3.6V VCC. Datasheet page 24 says
that 8
> MHz can
> | > be run at VCC greater than 2.8 Volts.
> | >
> | > mago
> | >
> | >
> | > markcrowptm > wrote:
> | > On my project, VCC can run from 1.8V to 3.3V and my oscillator
is 8
> | > MHz. Unfortunately I'm not in a position make any hardware
changes.
> | > The data sheet for the MSP430F1611 seems to indicate that the
micro can
> | > only run at 8 MHz if VCC is 3.6V. It indicates I can run with
my VCC
> | > issues at 4 MHz. Can I then simply program the clock control
register
> | > BCSCTL2 to divide MCLK by 2 and solve the problem?
> | >
> | > Thanks in advance.
> | >
> | > ---------------------------------
> | > Need Mail bonding?
> | > Go to the Yahoo! Mail Q&A for great tips from Yahoo! Answers
users.
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | >
> | > >
> egroups.com
> | >
> | >
> | > Yahoo! Groups Links
> | >
> | >
> | >
> | >
> |
> |
> |
> |
> |
> |
> |
> | Yahoo! Groups Links
> |
> |
> |
>
Yahoo! Groups Links
