Lpc2000

Hi All,

I am having difficulty with controlling pin P0.2 as a GPIO output 
signal. I am successfully controlling several other pins on my board. 
I have set bit 4 and 5 of PINSEL0 to zero. I have set bit 2 of IO0DIR 
to 1 and I have set bit 2 of IO0SET to 1. P0.2 stays at zero. I have 
used the same procedure on other pins with success. Is there 
something I am missing?  

Thanks,
Bob Davis

--- In lpc2000@yahoogroups.com, "rkd0930home" <rkd0930@c...> wrote:
> Hi All,
> 
> I am having difficulty with controlling pin P0.2 as a GPIO output 
> signal. I am successfully controlling several other pins on my 
board. 
> I have set bit 4 and 5 of PINSEL0 to zero. I have set bit 2 of 
IO0DIR 
> to 1 and I have set bit 2 of IO0SET to 1. P0.2 stays at zero. I 
have 
> used the same procedure on other pins with success. Is there 
> something I am missing?  
> 
> Thanks,
> Bob Davis

I just found a previous email on the issue and I now know that this 
pin is an open collector output. Thanks anyway.

Bob Davis

Read the I2C documentation in the user manual.  P0.02 and P0.03 are open
drain pins.  You need a pull-up.  (Been there, done that, got the
T-shirt!)

-----Original Message-----
From: rkd0930home [mailto:rkd0930@...] 
Sent: Tuesday, July 27, 2004 6:46 AM
To: lpc2000@yahoogroups.com
Subject: [lpc2000] Trouble with P0.2 as GPIO


Hi All,

I am having difficulty with controlling pin P0.2 as a GPIO output 
signal. I am successfully controlling several other pins on my board. 
I have set bit 4 and 5 of PINSEL0 to zero. I have set bit 2 of IO0DIR 
to 1 and I have set bit 2 of IO0SET to 1. P0.2 stays at zero. I have 
used the same procedure on other pins with success. Is there 
something I am missing?  

Thanks,
Bob Davis 




 
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At 01:45 PM 7/27/04 +0000, you wrote:
>I am having difficulty with controlling pin P0.2 as a GPIO output
>signal. I am successfully controlling several other pins on my board.
>I have set bit 4 and 5 of PINSEL0 to zero. I have set bit 2 of IO0DIR
>to 1 and I have set bit 2 of IO0SET to 1. P0.2 stays at zero. I have
>used the same procedure on other pins with success. Is there
>something I am missing?

That's one of the I2C pins, do you have a pull-up on it?

Robert

" 'Freedom' has no meaning of itself.  There are always restrictions,
be they legal, genetic, or physical.  If you don't believe me, try to
chew a radio signal. "

                         Kelvin Throop, III

Which lpc eval board u are u using? I wouldn't mind viewing the 
schematic to see how P0.2's connected to everything.

It would be very wierd if P0.2 stays low when set, even if the pin's 
not connected to any circuit.


--- In lpc2000@yahoogroups.com, "rkd0930home" <rkd0930@c...> wrote:
> Hi All,
> 
> I am having difficulty with controlling pin P0.2 as a GPIO output 
> signal. I am successfully controlling several other pins on my 
board. 
> I have set bit 4 and 5 of PINSEL0 to zero. I have set bit 2 of 
IO0DIR 
> to 1 and I have set bit 2 of IO0SET to 1. P0.2 stays at zero. I 
have 

> used the same procedure on other pins with success. Is there 
> something I am missing?  
> 
> Thanks,
> Bob Davis