Just need to clarify...

[Demon]

i is the bit index. PORTB.0[i] = 0 is PORTB.BIT[i] = 0. i increments from 0 to 7, so it clears
PORTB.0 to PORTB.7.

I'm happy you posted this question tazntex. I never used the REPEAT instruction, but as a programmer I know I would have fallen into one of those see-what-you-want traps, something like this:

i = 0
REPEAT
PORTB.[i] = 0
i = i + 1
UNTIL i > 7

I would have looked at this code for hours before seeing where I went wrong.


(I wished we had a button that allowed us to use the CODE command, I can never remember the syntax.)

[Heckler]

I for one have called the good people over at MElabs and requested(suggested) that they spend more effort on better syntax examples in the manual. Why waste all those clean white pages? (They agreed, by the way)

As I look at this example it still does not make sense to me.
I would have tried it the same as Robert, and banged my head against the wall for hours...

This one does not look intuitive at all.

Thanks for the heads up...

Dwight

[rsocor01]

Tazntex,

In your first post you said

I understand how it repeats until i is equal to 7 then moves on but what does the [i] in PORTB.0[i] do?

Technically speaking, it repeats until I=8 then it exits the loop. Of course, it won't execute the line PORT[I]=0 for I=8.

Robert

[tazntex]

Thanks goes to all for you help and interest.

[MOUNTAIN747]

While were on the subject of Port.Bits. I would like to use a random generator to set a single bit in an output port while working with an 8x8 dot matrix display. Is there any way to use a VARiable to set a RANDOM single Bit on an output port?

[aratti]

Is there any way to use a VARiable to set a RANDOM single Bit on an output port?

Ran_Word var word

Ini:
RANDOM Ran_Word
pause 100
PortB = Ran_Word.byte0
Pause 100
PortB = Ran_Word.byte1
Goto Ini

This code should suite your need.

Al.

[MOUNTAIN747]

Al, thanks for your replay. I ran your code. it sets the whole port at a random value. I need to figure out how to set a single bit within the port. I want to turn on a single led on the 8x8 display, then PAUSE, then loop to routine. Any idea how to single out one bit randomized?