I'm not sure, but I do save whales all the time - I've been saving one
for over 6 months and it's
gone quite smelly ...
Best Regards,
Kris
-----Original Message-----
From: m... [mailto:m...] On Behalf Of One Stone
Sent: Thursday, 21 February 2008 11:50 AM
To: m...
Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
AL
microbit wrote:
>And stop the whale killing :-)
>
>Best Regards,
>Kris
>
>-----Original Message-----
>From: m... [mailto:m...] On Behalf Of Steve Sabram
>Sent: Thursday, 21 February 2008 9:49 AM
>To: m...
>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>
>And if this project was outsourced, you get what you pay for.
>
>Steve
ADC12 calibration for MSP430F149
Started by ●February 20, 2008
Reply by ●February 20, 20082008-02-20
Reply by ●February 20, 20082008-02-20
How the hell do you get them through the slot in the piggy bank? I had
this problem with Save the Children, I had to slice the little buggers
up to get them through the slot.
Al
microbit wrote:
>I'm not sure, but I do save whales all the time - I've been saving one for over 6 months and it's
>gone quite smelly ...
>
>Best Regards,
>Kris
>-----Original Message-----
>From: m... [mailto:m...] On Behalf Of One Stone
>Sent: Thursday, 21 February 2008 11:50 AM
>To: m...
>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>
>WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
>
>AL
>
>microbit wrote:
>
>
>
>>And stop the whale killing :-)
>>
>>Best Regards,
>>Kris
>>
>>-----Original Message-----
>>From: m... [mailto:m...] On Behalf Of Steve Sabram
>>Sent: Thursday, 21 February 2008 9:49 AM
>>To: m...
>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>>
>>And if this project was outsourced, you get what you pay for.
>>
>>Steve
>>
>
this problem with Save the Children, I had to slice the little buggers
up to get them through the slot.
Al
microbit wrote:
>I'm not sure, but I do save whales all the time - I've been saving one for over 6 months and it's
>gone quite smelly ...
>
>Best Regards,
>Kris
>-----Original Message-----
>From: m... [mailto:m...] On Behalf Of One Stone
>Sent: Thursday, 21 February 2008 11:50 AM
>To: m...
>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>
>WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
>
>AL
>
>microbit wrote:
>
>
>
>>And stop the whale killing :-)
>>
>>Best Regards,
>>Kris
>>
>>-----Original Message-----
>>From: m... [mailto:m...] On Behalf Of Steve Sabram
>>Sent: Thursday, 21 February 2008 9:49 AM
>>To: m...
>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>>
>>And if this project was outsourced, you get what you pay for.
>>
>>Steve
>>
>
Reply by ●February 20, 20082008-02-20
Sushimi !!!
Best Regards,
Kris
-----Original Message-----
From: m... [mailto:m...] On Behalf Of One Stone
Sent: Thursday, 21 February 2008 12:06 PM
To: m...
Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
How the hell do you get them through the slot in the piggy bank? I had
this problem with Save the Children, I had to slice the little buggers
up to get them through the slot.
Al
microbit wrote:
>I'm not sure, but I do save whales all the time - I've been saving one for over 6 months and it's
>gone quite smelly ...
>
>Best Regards,
>Kris
>-----Original Message-----
>From: m... [mailto:m...] On Behalf Of One Stone
>Sent: Thursday, 21 February 2008 11:50 AM
>To: m...
>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>
>WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
>
>AL
>
>microbit wrote:
>
>
>
>>And stop the whale killing :-)
>>
>>Best Regards,
>>Kris
Best Regards,
Kris
-----Original Message-----
From: m... [mailto:m...] On Behalf Of One Stone
Sent: Thursday, 21 February 2008 12:06 PM
To: m...
Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
How the hell do you get them through the slot in the piggy bank? I had
this problem with Save the Children, I had to slice the little buggers
up to get them through the slot.
Al
microbit wrote:
>I'm not sure, but I do save whales all the time - I've been saving one for over 6 months and it's
>gone quite smelly ...
>
>Best Regards,
>Kris
>-----Original Message-----
>From: m... [mailto:m...] On Behalf Of One Stone
>Sent: Thursday, 21 February 2008 11:50 AM
>To: m...
>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>
>WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
>
>AL
>
>microbit wrote:
>
>
>
>>And stop the whale killing :-)
>>
>>Best Regards,
>>Kris
Reply by ●February 20, 20082008-02-20
Have you checked status, a Rx_FIFO overflow or Tx_FIFO undeflow will
cause this to happen.
Al
One Stone wrote:
>How the hell do you get them through the slot in the piggy bank? I had
>this problem with Save the Children, I had to slice the little buggers
>up to get them through the slot.
>
>Al
>
>microbit wrote:
>
>
>
>>I'm not sure, but I do save whales all the time - I've been saving one for over 6 months and it's
>>gone quite smelly ...
>>
>>Best Regards,
>>Kris
>>-----Original Message-----
>>From: m... [mailto:m...] On Behalf Of One Stone
>>Sent: Thursday, 21 February 2008 11:50 AM
>>To: m...
>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>>
>>WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
>>
>>AL
>>
>>microbit wrote:
>>
>>
>>
>>>And stop the whale killing :-)
>>>
>>>Best Regards,
>>>Kris
>>>
>>>-----Original Message-----
>>>From: m... [mailto:m...] On Behalf Of Steve Sabram
>>>Sent: Thursday, 21 February 2008 9:49 AM
>>>To: m...
>>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>>>
>>>And if this project was outsourced, you get what you pay for.
>>>
>>>Steve
>>>
>>>
>>>
>
cause this to happen.
Al
One Stone wrote:
>How the hell do you get them through the slot in the piggy bank? I had
>this problem with Save the Children, I had to slice the little buggers
>up to get them through the slot.
>
>Al
>
>microbit wrote:
>
>
>
>>I'm not sure, but I do save whales all the time - I've been saving one for over 6 months and it's
>>gone quite smelly ...
>>
>>Best Regards,
>>Kris
>>-----Original Message-----
>>From: m... [mailto:m...] On Behalf Of One Stone
>>Sent: Thursday, 21 February 2008 11:50 AM
>>To: m...
>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>>
>>WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
>>
>>AL
>>
>>microbit wrote:
>>
>>
>>
>>>And stop the whale killing :-)
>>>
>>>Best Regards,
>>>Kris
>>>
>>>-----Original Message-----
>>>From: m... [mailto:m...] On Behalf Of Steve Sabram
>>>Sent: Thursday, 21 February 2008 9:49 AM
>>>To: m...
>>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>>>
>>>And if this project was outsourced, you get what you pay for.
>>>
>>>Steve
>>>
>>>
>>>
>
Reply by ●February 20, 20082008-02-20
Can the outside owner give any information to help you?
Emmett Redd Ph.D. mailto:E...@missouristate.edu
Professor (417)836-5221
Department of Physics, Astronomy, and Materials Science
Missouri State University Fax (417)836-6226
901 SOUTH NATIONAL Dept (417)836-5131
SPRINGFIELD, MO 65897 USA
How much wood would a woodchuck chuck if a woodchuck could chuck wood?
How much ground would a groundhog hog if a groundhog could hog ground?
How much pig would a whistlepig whistle if a whistlepig could whistle
pig? :-\ :-/ :-)
________________________________
From: m... on behalf of barion79
Sent: Wed 2/20/2008 12:45 PM
To: m...
Subject: [msp430] Re: ADC12 calibration for MSP430F149
Thank you all for replying.
The solutions that you suggested I have already thought about.
However, the problem is that these solutions will work only with new
devices.
Unfortunately, at this moment I have many units outside. The only way
I can update those is by sending an updated FW. Thus, I need to find
a way to get a proper reading from ADC without having access to the
HW.
Maybe someone have an idea how accurate reading can be done without
having measured reference voltage?
Thank you,
Leon.
> I have run into an unexpected issue with getting exact value from
ADC.
>
> According to data sheets the internal VREF+ can fluctuate between
> 2.4V to 2.5V. In addition, the voltage regulator (3.3V) also
> fluctuates between 3.234V to 3.366V. Thus, different devices
provide
> me with different conversion data. This data often do not reach the
> required limit and the device does not work properly.
>
> Now the easiest solution would be to add external reference voltage
> to VeREF+. However the hardware design has been done before and
there
> are many device sent out. Thus, I need to provide a FW solution to
> such problem.
>
> Did anyone encountered this problem before and maybe has a quick
> solution.
>
> Thank you,
> Leon.
>
Emmett Redd Ph.D. mailto:E...@missouristate.edu
Professor (417)836-5221
Department of Physics, Astronomy, and Materials Science
Missouri State University Fax (417)836-6226
901 SOUTH NATIONAL Dept (417)836-5131
SPRINGFIELD, MO 65897 USA
How much wood would a woodchuck chuck if a woodchuck could chuck wood?
How much ground would a groundhog hog if a groundhog could hog ground?
How much pig would a whistlepig whistle if a whistlepig could whistle
pig? :-\ :-/ :-)
________________________________
From: m... on behalf of barion79
Sent: Wed 2/20/2008 12:45 PM
To: m...
Subject: [msp430] Re: ADC12 calibration for MSP430F149
Thank you all for replying.
The solutions that you suggested I have already thought about.
However, the problem is that these solutions will work only with new
devices.
Unfortunately, at this moment I have many units outside. The only way
I can update those is by sending an updated FW. Thus, I need to find
a way to get a proper reading from ADC without having access to the
HW.
Maybe someone have an idea how accurate reading can be done without
having measured reference voltage?
Thank you,
Leon.
> I have run into an unexpected issue with getting exact value from
ADC.
>
> According to data sheets the internal VREF+ can fluctuate between
> 2.4V to 2.5V. In addition, the voltage regulator (3.3V) also
> fluctuates between 3.234V to 3.366V. Thus, different devices
provide
> me with different conversion data. This data often do not reach the
> required limit and the device does not work properly.
>
> Now the easiest solution would be to add external reference voltage
> to VeREF+. However the hardware design has been done before and
there
> are many device sent out. Thus, I need to provide a FW solution to
> such problem.
>
> Did anyone encountered this problem before and maybe has a quick
> solution.
>
> Thank you,
> Leon.
>
Reply by ●February 21, 20082008-02-21
Al, I think you meant to replay to the "Strange CC1101 problem" post.
Altought it is a fun replay to this one.
Michael K.
--- In m..., One Stone wrote:
>
> Have you checked status, a Rx_FIFO overflow or Tx_FIFO undeflow will
> cause this to happen.
>
> Al
>
> One Stone wrote:
>
> >How the hell do you get them through the slot in the piggy bank? I had
> >this problem with Save the Children, I had to slice the little buggers
> >up to get them through the slot.
> >
> >Al
> >
> >microbit wrote:
> >
> >
> >
> >>I'm not sure, but I do save whales all the time - I've been saving
one for over 6 months and it's
> >>gone quite smelly ...
> >>
> >>Best Regards,
> >>Kris
> >>
> >>
> >>-----Original Message-----
> >>From: m... [mailto:m...] On
Behalf Of One Stone
> >>Sent: Thursday, 21 February 2008 11:50 AM
> >>To: m...
> >>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
> >>
> >>WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
> >>
> >>AL
> >>
> >>microbit wrote:
> >>
> >>
> >>
> >>
> >>
> >>>And stop the whale killing :-)
> >>>
> >>>Best Regards,
> >>>Kris
> >>>
> >>>-----Original Message-----
> >>>From: m... [mailto:m...] On
Behalf Of Steve Sabram
> >>>Sent: Thursday, 21 February 2008 9:49 AM
> >>>To: m...
> >>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
> >>>
> >>>And if this project was outsourced, you get what you pay for.
> >>>
> >>>Steve
> >>>
> >>>
> >>>
> >>>
> >>
> >>
> >>
> >>
> >>
Altought it is a fun replay to this one.
Michael K.
--- In m..., One Stone wrote:
>
> Have you checked status, a Rx_FIFO overflow or Tx_FIFO undeflow will
> cause this to happen.
>
> Al
>
> One Stone wrote:
>
> >How the hell do you get them through the slot in the piggy bank? I had
> >this problem with Save the Children, I had to slice the little buggers
> >up to get them through the slot.
> >
> >Al
> >
> >microbit wrote:
> >
> >
> >
> >>I'm not sure, but I do save whales all the time - I've been saving
one for over 6 months and it's
> >>gone quite smelly ...
> >>
> >>Best Regards,
> >>Kris
> >>
> >>
> >>-----Original Message-----
> >>From: m... [mailto:m...] On
Behalf Of One Stone
> >>Sent: Thursday, 21 February 2008 11:50 AM
> >>To: m...
> >>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
> >>
> >>WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
> >>
> >>AL
> >>
> >>microbit wrote:
> >>
> >>
> >>
> >>
> >>
> >>>And stop the whale killing :-)
> >>>
> >>>Best Regards,
> >>>Kris
> >>>
> >>>-----Original Message-----
> >>>From: m... [mailto:m...] On
Behalf Of Steve Sabram
> >>>Sent: Thursday, 21 February 2008 9:49 AM
> >>>To: m...
> >>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
> >>>
> >>>And if this project was outsourced, you get what you pay for.
> >>>
> >>>Steve
> >>>
> >>>
> >>>
> >>>
> >>
> >>
> >>
> >>
> >>
Reply by ●February 21, 20082008-02-21
Damn, gotta stay off those damned meds!!
Al
tintronic wrote:
>Al, I think you meant to replay to the "Strange CC1101 problem" post.
>Altought it is a fun replay to this one.
>
>Michael K.
>
>--- In m..., One Stone wrote:
>
>
>>Have you checked status, a Rx_FIFO overflow or Tx_FIFO undeflow will
>>cause this to happen.
>>
>>Al
>>
>>One Stone wrote:
>>
>>
>>
>>>How the hell do you get them through the slot in the piggy bank? I had
>>>this problem with Save the Children, I had to slice the little buggers
>>>up to get them through the slot.
>>>
>>>Al
>>>
>>>microbit wrote:
>>>
>>>
>>>
>>>
>>>
>>>>I'm not sure, but I do save whales all the time - I've been saving
>>>>
>>>>
>one for over 6 months and it's
>
>
>>>>gone quite smelly ...
>>>>
>>>>Best Regards,
>>>>Kris
>>>>
>>>>
>>>>-----Original Message-----
>>>>From: m... [mailto:m...] On
>>>>
>>>>
>Behalf Of One Stone
>
>
>>>>Sent: Thursday, 21 February 2008 11:50 AM
>>>>To: m...
>>>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>>>>
>>>>WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
>>>>
>>>>AL
>>>>
>>>>microbit wrote:
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>>And stop the whale killing :-)
>>>>>
>>>>>Best Regards,
>>>>>Kris
>>>>>
>>>>>-----Original Message-----
>>>>>From: m... [mailto:m...] On
>>>>>
>>>>>
>Behalf Of Steve Sabram
>
>
>>>>>Sent: Thursday, 21 February 2008 9:49 AM
>>>>>To: m...
>>>>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>>>>>
>>>>>And if this project was outsourced, you get what you pay for.
>>>>>
>>>>>Steve
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>>
Al
tintronic wrote:
>Al, I think you meant to replay to the "Strange CC1101 problem" post.
>Altought it is a fun replay to this one.
>
>Michael K.
>
>--- In m..., One Stone wrote:
>
>
>>Have you checked status, a Rx_FIFO overflow or Tx_FIFO undeflow will
>>cause this to happen.
>>
>>Al
>>
>>One Stone wrote:
>>
>>
>>
>>>How the hell do you get them through the slot in the piggy bank? I had
>>>this problem with Save the Children, I had to slice the little buggers
>>>up to get them through the slot.
>>>
>>>Al
>>>
>>>microbit wrote:
>>>
>>>
>>>
>>>
>>>
>>>>I'm not sure, but I do save whales all the time - I've been saving
>>>>
>>>>
>one for over 6 months and it's
>
>
>>>>gone quite smelly ...
>>>>
>>>>Best Regards,
>>>>Kris
>>>>
>>>>
>>>>-----Original Message-----
>>>>From: m... [mailto:m...] On
>>>>
>>>>
>Behalf Of One Stone
>
>
>>>>Sent: Thursday, 21 February 2008 11:50 AM
>>>>To: m...
>>>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>>>>
>>>>WHICH WHALE IS KILLING& AND WHO OR WHAT IS IT KILLING?
>>>>
>>>>AL
>>>>
>>>>microbit wrote:
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>>And stop the whale killing :-)
>>>>>
>>>>>Best Regards,
>>>>>Kris
>>>>>
>>>>>-----Original Message-----
>>>>>From: m... [mailto:m...] On
>>>>>
>>>>>
>Behalf Of Steve Sabram
>
>
>>>>>Sent: Thursday, 21 February 2008 9:49 AM
>>>>>To: m...
>>>>>Subject: Re: [msp430] Re: ADC12 calibration for MSP430F149
>>>>>
>>>>>And if this project was outsourced, you get what you pay for.
>>>>>
>>>>>Steve
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>>
Reply by ●February 21, 20082008-02-21
Hello All,
I would like to thank everyone who replied to this post. You just
confirmed what I have suspected in the beginning.
Unfortunately, I am a new engineer in the company that got stuck with
the project that was sorced out. So, I am screwed.
However, I would like to thank you guys for the whale, sushi and so
on answers. They made me feel a bit better. Hope this day will not
ruin the mood.
Thanks again.
Leon
--- In m..., "barion79" wrote:
>
> Hello All,
>
> I have run into an unexpected issue with getting exact value from
ADC.
>
> According to data sheets the internal VREF+ can fluctuate between
> 2.4V to 2.5V. In addition, the voltage regulator (3.3V) also
> fluctuates between 3.234V to 3.366V. Thus, different devices
provide
> me with different conversion data. This data often do not reach the
> required limit and the device does not work properly.
>
> Now the easiest solution would be to add external reference voltage
> to VeREF+. However the hardware design has been done before and
there
> are many device sent out. Thus, I need to provide a FW solution to
> such problem.
>
> Did anyone encountered this problem before and maybe has a quick
> solution.
>
> Thank you,
> Leon.
>
I would like to thank everyone who replied to this post. You just
confirmed what I have suspected in the beginning.
Unfortunately, I am a new engineer in the company that got stuck with
the project that was sorced out. So, I am screwed.
However, I would like to thank you guys for the whale, sushi and so
on answers. They made me feel a bit better. Hope this day will not
ruin the mood.
Thanks again.
Leon
--- In m..., "barion79" wrote:
>
> Hello All,
>
> I have run into an unexpected issue with getting exact value from
ADC.
>
> According to data sheets the internal VREF+ can fluctuate between
> 2.4V to 2.5V. In addition, the voltage regulator (3.3V) also
> fluctuates between 3.234V to 3.366V. Thus, different devices
provide
> me with different conversion data. This data often do not reach the
> required limit and the device does not work properly.
>
> Now the easiest solution would be to add external reference voltage
> to VeREF+. However the hardware design has been done before and
there
> are many device sent out. Thus, I need to provide a FW solution to
> such problem.
>
> Did anyone encountered this problem before and maybe has a quick
> solution.
>
> Thank you,
> Leon.
>
Reply by ●February 21, 20082008-02-21
It depends on your definition of fluctuates. I am guessing you mean it
is a certain value that is different on each board, and not that the
noise means it changes second by second.
What you will have to do is calibrate. Either you measure the values at
manufacture and put it in EEPROM, or you measure known values and
calculate the factors out.
I have a wave form generator, that went from +140V to -140V. I set up a
routine that put out 16 values through out the range, and as it set each
value, I typed in what the volt meter read, then it moved to the next
setting. When I was finished I did a least squares linear match, to get
the slope and offset for the match. Then I had it test the voltage at
every 10 volts from 140 to -140. This was a quick visual check to see if
I accidentally typed in a number incorrectly.
Kip
On Wed, 2008-02-20 at 16:26 +0000, barion79 wrote:
> Hello All,
>
> I have run into an unexpected issue with getting exact value from ADC.wrong
>
> According to data sheets the internal VREF+ can fluctuate between
> 2.4V to 2.5V. In addition, the voltage regulator (3.3V) also
> fluctuates between 3.234V to 3.366V. Thus, different devices provide
> me with different conversion data. This data often do not reach the
> required limit and the device does not work properly.
>
> Now the easiest solution would be to add external reference voltage
> to VeREF+. However the hardware design has been done before and there
> are many device sent out. Thus, I need to provide a FW solution to
> such problem.
>
> Did anyone encountered this problem before and maybe has a quick
> solution.
>
> Thank you,
> Leon.
>
>
is a certain value that is different on each board, and not that the
noise means it changes second by second.
What you will have to do is calibrate. Either you measure the values at
manufacture and put it in EEPROM, or you measure known values and
calculate the factors out.
I have a wave form generator, that went from +140V to -140V. I set up a
routine that put out 16 values through out the range, and as it set each
value, I typed in what the volt meter read, then it moved to the next
setting. When I was finished I did a least squares linear match, to get
the slope and offset for the match. Then I had it test the voltage at
every 10 volts from 140 to -140. This was a quick visual check to see if
I accidentally typed in a number incorrectly.
Kip
On Wed, 2008-02-20 at 16:26 +0000, barion79 wrote:
> Hello All,
>
> I have run into an unexpected issue with getting exact value from ADC.wrong
>
> According to data sheets the internal VREF+ can fluctuate between
> 2.4V to 2.5V. In addition, the voltage regulator (3.3V) also
> fluctuates between 3.234V to 3.366V. Thus, different devices provide
> me with different conversion data. This data often do not reach the
> required limit and the device does not work properly.
>
> Now the easiest solution would be to add external reference voltage
> to VeREF+. However the hardware design has been done before and there
> are many device sent out. Thus, I need to provide a FW solution to
> such problem.
>
> Did anyone encountered this problem before and maybe has a quick
> solution.
>
> Thank you,
> Leon.
>
>
Reply by ●February 22, 20082008-02-22
You may be able to improve things. First, describe your measurement
circuit and exactly what you are measuring. By this I am looking for
whether it is ratiometric, such as a resistive sensor primarily
excited by the Vcc of the MSP430, or is it derived from some fixed
reference (possibly derived from a source outside your equipment).
The more description you can provide here the better. Then maybe I
can give you some suggestions on fixing your problem, either by
changing your sampling or incorporation of some filtering/scaling to
provide auto-calibration.
Regards, Hugh
At 10:45 AM 2/20/2008, you wrote:
Thank you all for replying.
The solutions that you suggested I have already thought about.
However, the problem is that these solutions will work only with new
devices.
Unfortunately, at this moment I have many units outside. The only way
I can update those is by sending an updated FW. Thus, I need to find
a way to get a proper reading from ADC without having access to the
HW.
Maybe someone have an idea how accurate reading can be done without
having measured reference voltage?
Thank you,
Leon.
> I have run into an unexpected issue with getting exact value from
ADC.
>
> According to data sheets the internal VREF+ can fluctuate between
> 2.4V to 2.5V. In addition, the voltage regulator (3.3V) also
> fluctuates between 3.234V to 3.366V. Thus, different devices
provide
> me with different conversion data. This data often do not reach the
> required limit and the device does not work properly.
>
> Now the easiest solution would be to add external reference voltage
> to VeREF+. However the hardware design has been done before and
there
> are many device sent out. Thus, I need to provide a FW solution to
> such problem.
>
> Did anyone encountered this problem before and maybe has a quick
> solution.
>
> Thank you,
> Leon.
>
circuit and exactly what you are measuring. By this I am looking for
whether it is ratiometric, such as a resistive sensor primarily
excited by the Vcc of the MSP430, or is it derived from some fixed
reference (possibly derived from a source outside your equipment).
The more description you can provide here the better. Then maybe I
can give you some suggestions on fixing your problem, either by
changing your sampling or incorporation of some filtering/scaling to
provide auto-calibration.
Regards, Hugh
At 10:45 AM 2/20/2008, you wrote:
Thank you all for replying.
The solutions that you suggested I have already thought about.
However, the problem is that these solutions will work only with new
devices.
Unfortunately, at this moment I have many units outside. The only way
I can update those is by sending an updated FW. Thus, I need to find
a way to get a proper reading from ADC without having access to the
HW.
Maybe someone have an idea how accurate reading can be done without
having measured reference voltage?
Thank you,
Leon.
> I have run into an unexpected issue with getting exact value from
ADC.
>
> According to data sheets the internal VREF+ can fluctuate between
> 2.4V to 2.5V. In addition, the voltage regulator (3.3V) also
> fluctuates between 3.234V to 3.366V. Thus, different devices
provide
> me with different conversion data. This data often do not reach the
> required limit and the device does not work properly.
>
> Now the easiest solution would be to add external reference voltage
> to VeREF+. However the hardware design has been done before and
there
> are many device sent out. Thus, I need to provide a FW solution to
> such problem.
>
> Did anyone encountered this problem before and maybe has a quick
> solution.
>
> Thank you,
> Leon.
>
