Lpc2000

I am reading two different defintions regarding the funtion of 
pin#10 on an LPC2131 in the User Manual.  In Table 48 pin#10 (P0.26)
is defined as AD0.5,or AD converter 0, input 5.  But, in Table 51: 
the Pin Function Select Register (PINSEL1), P0.26 is defined as 
reserved, meaning it can not be used for anything?

Which is it?  I really need another ADC input, so if P0.26 is indeed 
an AD input, great.  Otherwise, if it is reserved, I will have to 
figure something else out.

Can anyone please help!!

Thanks,
Dave

Hi Dave,
  Your right! I am assuming that since that input is an dedicated ADC
input, that is would be considered reserved for that reason.

regards,
Charles


--- In lpc2000@yahoogroups.com, "drb5599" <dbutler@c...> wrote:

> 
> I am reading two different defintions regarding the funtion of 
> pin#10 on an LPC2131 in the User Manual.  In Table 48 pin#10 (P0.26)
> is defined as AD0.5,or AD converter 0, input 5.  But, in Table 51: 
> the Pin Function Select Register (PINSEL1), P0.26 is defined as 
> reserved, meaning it can not be used for anything?
> 
> Which is it?  I really need another ADC input, so if P0.26 is indeed 
> an AD input, great.  Otherwise, if it is reserved, I will have to 
> figure something else out.
> 
> Can anyone please help!!
> 
> Thanks,
> Dave

As I understand it - the inputs are ALWAYS available for the A/D.

Owen

From the User manual:

The only partial exception from the above rule of exclusion is the case of inputs to the A/D converter. Regardless of the function that is selected for the port pin that also hosts the A/D input, this A/D input can be read at any time and variations of the voltage level on this pin will be reflected in the A/D readings. However, valid analog  reading(s) can be obtained if and only if the function of an analog input is selected. Only in this case proper interface circuit is active in between the physical pin and the A/D module. In all other cases, a part of digital logic necessary for the digital function to be performed will be active, and will disrupt proper behavior of the A/D.


Hi Dave,
  Your right! I am assuming that since that input is an dedicated ADC
input, that is would be considered reserved for that reason.

regards,
Charles


--- In lpc2000@yahoogroups.com, "drb5599" <dbutler@c...> wrote:

>> 
>> I am reading two different defintions regarding the funtion of 
>> pin#10 on an LPC2131 in the User Manual.  In Table 48 pin#10 (P0.26)
>> is defined as AD0.5,or AD converter 0, input 5.  But, in Table 51: 
>> the Pin Function Select Register (PINSEL1), P0.26 is defined as 
>> reserved, meaning it can not be used for anything?
>> 
>> Which is it?  I really need another ADC input, so if P0.26 is indeed 
>> an AD input, great.  Otherwise, if it is reserved, I will have to 
>> figure something else out.
>> 
>> Can anyone please help!!
>> 
>> Thanks,
>> Dave
>  
>

Look at Table 7 in the Data Sheet.  I assume that this is the correct 
information, and Table 51 of the User Manual is wrong.

I have been told that, in general, the Preliminary Data Sheet is more 
accurate than the Preliminary User Manual (even though the date is a 
few days earlier).



--- In lpc2000@yahoogroups.com, "drb5599" <dbutler@c...> wrote:
> 
> I am reading two different defintions regarding the funtion of 
> pin#10 on an LPC2131 in the User Manual.  In Table 48 pin#10 (P0.26)
> is defined as AD0.5,or AD converter 0, input 5.  But, in Table 51: 
> the Pin Function Select Register (PINSEL1), P0.26 is defined as 
> reserved, meaning it can not be used for anything?
> 
> Which is it?  I really need another ADC input, so if P0.26 is 
indeed 

> an AD input, great.  Otherwise, if it is reserved, I will have to 
> figure something else out.
> 
> Can anyone please help!!
> 
> Thanks,
> Dave