FOR...NEXT strange counting

[mister_e]

OK i'll try another explanation

    For Variable=0 to 255
        Pouet pouet
        next

The test is done at the FOR TO NEXT line, the incrementation is done at NEXT line.
So at the end the value=256... wich is really hard to fit in a BYTE variable. Hence it gives 0

Change your var to a WORD too see what's happen now.

    Repeat
        Pouet Pouet
        Variable = Variable +1
        Until Variable = 255

a Repeat Untill loop do the test at the end... so this why it worked

[flotulopex]

Thank you All,

All your explanations are absolutely clear.

[peterdeco1]

Hi Flotulopex. The FOR - NEXT is confusing to me too. I use a different routine from a basic compiler I used a long time ago. This is a snip from a motor speed controller that controls the speed of an electric cart. At the start of the program, LEFTRAMP is made 0. If the speedpot is reduced while running, it will also ramp down.

LEFTON: 'TURNS ON LEFT MOTOR FOR RIGHT TURN
ADCIN 2, SPEEDPOT
IF LEFTRAMP < SPEEDPOT Then LET LEFTRAMP = LEFTRAMP + 1
IF LEFTRAMP > SPEEDPOT Then LET LEFTRAMP = LEFTRAMP - 1
Pause 1 'CONTROLS THE RAMP-UP DELAY
HPwm 1,LEFTRAMP,15000 'PWM OUTPUT DUTYCYCLE LIMITED TO SPEEDPOT
GoTo LEFTON