Lpc2000

Hi Tom,

  Thanks for the reminder! I always used a port image for outputs, but
since it worked fine on the LPC2106, I assumed .......... Oh well.

regards,
Charles

--- In lpc2000@yahoogroups.com, Tom Walsh <tom@...> wrote:
>
> charlesgrenz wrote:
> 
> >Hello group,
> >
> >  Have a strange problem. The following code works perfectly on a
LPC2106.
> >
> >    if (((T1IR & T1IR_MR2INT) != 0) || (T1MR2 < T1TC)) // Timer 1,
> >Match 2 - 500ms LED Delay <<<<<<<<<<<<<<<<<<<<<<
> >       {
> >        T1MR2 = T1TC + DEFAULT_TMR1_MR2_TIMEBASE; // Count up to this
> >value. Generate 2 Hz interrupt.
> >                    if ((IOPIN & POWER_LED) == 0)
> >                       {
> >                        IOSET = POWER_LED;
> >                       }
> >                    else
> >                       {
> >                        IOCLR = POWER_LED;
> >                       }
> >       }
> >
> >  
> >
> FWIW, as a matter of programming style, I always have the pin reflect a 
> variable state.  I don't have any reason, other than the pin port 
> structures of some processors read the value of the pin Latch as
opposed 
> to the actual value at the pin.  IIRC, 8051 was like this.
> 
> Having said that, never assume.  Are you measuring the actual
voltage at 
> that pin?  Are you assuming that since the LED is on / off that the pin 
> voltage would be considered a 0 or 1 state?
> 
> OH!  and another thing, there may be something where the pin is 
> programmed to an output state and there is no way to read the actual 
> value of the pin / pin latch (always returns a 0 or 1).
> 
> Like I said, what you are doing is a bit unusual as far as common 
> practice is concerned.
> 
> 
> TomW
> 
> -- 
> Tom Walsh - WN3L - Embedded Systems Consultant
> http://openhardware.net, http://cyberiansoftware.com
> "Windows? No thanks, I have work to do..."
> ----------------------------------------------------
>