Addressing individual O/P pins.

Hi there,

I have the BV500 setup and have been looking through the tutorials. I have a problem that I'm struggling to solve.

If I connect three LED's to Port A RA0 - 1 - 2; How can I activate the output pins individually? I have tried using LATAINV variable name and LATASET.

I use constants to define the LED's i.e:

constant LED 1 << 0
constant LED2 1 << 1
constant LED3 1 << 2

Then in the main function,

while loop

LATAINV LED
LATAINV LED2
LATAINV LED3

close loop

Thanks.

LATAINV is an address, you need to change the contents of the address using @, thus:
@LATAINV=LED
or
poke(LATAINV,LED)

My apologies, I was using @ in my code:

@LATAINV = LED
@LATAINV = LED2
@LATAINV = LED3

That is the code I was using above. But nothing happens except that the LED connected to RA0 flashes on and off.
I'm not getting any response from the LEDs connected to RA1 or RA2.

* Have you set RA1 and RA2 to be output using TRISA or TRISACLR?
* Is RA1 or 2 an analogue? If so they need setting to digital

Before the main function I have;

TRISACLR = 1
ANSELACLR = 1

Should be
@TRISACLR = 1
@ANSELACLR = 1

constant LED 1 << 0
constant LED2 1 << 1
constant LED3 1 << 2


@ANSELACLR = 1
@TRISACLR = 1



while loop

@LATAINV LED
@LATAINV LED2
@LATAINV LED3

close loop



This is my code summarised, I have the register addresses with the @ all set to digital.
I tried doing this on PORT B (I altered the addresses) and I would only get the same result. LED will flash but LED2 and LED3 are non responsive.

I've tested the LED's they all work.

I'm at a loss....

The code shoule look something like this:

function x()
  @ANSELACLR = 1
  @TRISACLR = LED2 | LED3
  while comkey?(2) = 0
     @LATAINV = LED
     @LATAINV = LED2
     @LATAINV= LED3 
     wait(200)
  wend
endf

This will work if all the constant values are correct and the pins are connected okay, if not then you need to keep checking, it is very easy to miss something. Try using LATACLR and LATASET instead, look at the current value in LATA, PORTA and in TRISA, is it what is expected? You can do this interactively, that's what makes debugging so easy.

Magic thanks!

That's done the trick.