Sequence of statements makes code work differently. (PIC16F628A)

[CuriousOne]

Hello,

below is the super simple code

SIKO:
HIGH PORTA.0
HIGH PORTA.1
PAUSE 500
LOW PORTA.0
LOW PORTA.1
PAUSE 500
GOTO SIKO

There are leds connected to porta.1 and porta.0

The above code works, but only first line

If I place at first line code for PORTA.0 it works, but next line, for PORTA.1 does not works. If I swap them, then PORTA.1 will work, but PORTA.0 - not. But if I modify code a bit, to look like this, then it works properly.

SIKO:
HIGH PORTA.0
PAUSE 500
LOW PORTA.0
HIGH PORTA.1
PAUSE 500
LOW PORTA.1
GOTO SIKO

[/code]


Why this happens?

I have no TRISA, etc defined, as manual told us, HIGH/LOW statement in PBP does all necessary, so this is why it is so slow, but it appears not to work?

[Jerson]

Without seeing your schematic, my guess would be the Read-Modify-Write issue documented in the data sheet. Try to write to PORTA as a whole rather than in bits to confirm this is the issue.

[CuriousOne]

Resistor-led-pin, that's all

[CuriousOne]

Strange, and how to write PORTA in whole? like this?

PORTA=%00000001

?

[CuriousOne]

It does not work, even setting PORTA.1=1 does nothing

[Demon]

Try

SIKO:
PORTA=%00000011
PAUSE 500
PORTA=%00000000
PAUSE 500
GOTO SIKO

[HenrikOlsson]

Everybody together now:
Remember to disable analog functions...
Remember to disable analog functions...
Remember to disable analog functions...

/Henrik.