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A/D converter of LPC2129

Started by daniela_boyo September 2, 2004
Hi everyone,

I'm having some problems with using the A/D converter of the LPC2129
ARM board. I'm interfacing the board with an LM35DZ temperature
sensor which has an output voltage proportional to the required
temperature (eg 0.68V is equal to 68 degrees C).

I have set up the A/D control as follows:

ADCR = 0x00270601
ADCR |= 0x01000000

Is the above set up suitable? Also, assuming I have gotten a value
from the A/D data (ADDR), how do I extract this value and get a
suitable value for the temperature (i.e. if analogue input is 0.25V
for instance)?

I would greatly appreciate it if someone can help me with this or if
someone is willing to share some example code.

Thank you!
Daniela.




An Engineer's Guide to the LPC2100 Series

here's the code im using:

for setting it up, using a PCLK of 60Mhz

ADCR = 0x00210E01; set up ADC AIN0, @PCLK/15 =4MHz, 10bit
ADCR = 0x01000000;

to read the ADC:
int value;
if (ADDR & 0x80000000) // wait for the conversion to finish
{
value = ADDR;
value = ((value>>6) & 0x03FF); // extract the data
} and thats it... dont forguet to set up the pin as ADC.
-----Original Message-----
From: daniela_boyo [mailto:]
Sent: 02 September 2004 12:24
To:
Subject: [lpc2000] A/D converter of LPC2129 Hi everyone,

I'm having some problems with using the A/D converter of the LPC2129
ARM board. I'm interfacing the board with an LM35DZ temperature
sensor which has an output voltage proportional to the required
temperature (eg 0.68V is equal to 68 degrees C).

I have set up the A/D control as follows:

ADCR = 0x00270601
ADCR |= 0x01000000

Is the above set up suitable? Also, assuming I have gotten a value
from the A/D data (ADDR), how do I extract this value and get a
suitable value for the temperature (i.e. if analogue input is 0.25V
for instance)?

I would greatly appreciate it if someone can help me with this or if
someone is willing to share some example code.

Thank you!
Daniela.

Yahoo! Groups Links



Hi,

Thanks very much for your help.

I tried out the code you sent and it works perfectly!

Best regards,

Daniela. --- In , "Fuentes Rodriguez, M.E." <mef6@l...>
wrote:
> here's the code im using:
>
> for setting it up, using a PCLK of 60Mhz
>
> ADCR = 0x00210E01; set up ADC AIN0, @PCLK/15 =4MHz, 10bit
> ADCR = 0x01000000;
>
> to read the ADC:
> int value;
> if (ADDR & 0x80000000) // wait for the conversion to finish
> {
> value = ADDR;
> value = ((value>>6) & 0x03FF); // extract the data
> } > and thats it... dont forguet to set up the pin as ADC. >
> -----Original Message-----
> From: daniela_boyo [mailto:dob3@l...]
> Sent: 02 September 2004 12:24
> To:
> Subject: [lpc2000] A/D converter of LPC2129 > Hi everyone,
>
> I'm having some problems with using the A/D converter of the
LPC2129
> ARM board. I'm interfacing the board with an LM35DZ temperature
> sensor which has an output voltage proportional to the required
> temperature (eg 0.68V is equal to 68 degrees C).
>
> I have set up the A/D control as follows:
>
> ADCR = 0x00270601
> ADCR |= 0x01000000
>
> Is the above set up suitable? Also, assuming I have gotten a value
> from the A/D data (ADDR), how do I extract this value and get a
> suitable value for the temperature (i.e. if analogue input is 0.25V
> for instance)?
>
> I would greatly appreciate it if someone can help me with this or
if
> someone is willing to share some example code.
>
> Thank you!
> Daniela. >
>
> Yahoo! Groups Links





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