servo motor resets 16f877a

[Acetronics2]

Ok, Folks

I've got it ...

Servo driving values on C.2 go out of the nominal 0.8 - 2.2 ms range OR Pause between pulses goes wrong.

Servo bumps on its mechanical stops ... or the amp doesnt like the pause !!!

That's all !

Alain

[burak450]

Acetronics,
Can you explain it more clear,i dont get what you mean.Is there any solution on your mind?

[Acetronics2]

Hi, Burak

The only solution is for you to verify you send correct signals to your servo ...

800 to 2200 µs @ 35 - 50 Hz ... only allowed.

Nothing more or less to say !

Alain

[burak450]

Hi Acetronics,
I think you are wrong because my signal is 50hz.I am using 20ms periodic pulses,if t=100 then 1ms high and 19ms low.if the period 20ms then frequency will be 50hz from the formula f=(1/T)
here is my signal code

PULSOUT PORTC.2,T
PAUSEUS 20000-(T*10)

where am I wrong?

[skimask]

Hi Acetronics,
I think you are wrong because my signal is 50hz.I am using 20ms periodic pulses,if t=100 then 1ms high and 19ms low.if the period 20ms then frequency will be 50hz from the formula f=(1/T)
here is my signal code

PULSOUT PORTC.2,T
PAUSEUS 20000-(T*10)

where am I wrong?

Look at the loop in your code.
Aboslutely no 'bounds' checking.
What if...T = 0? Then pauseus = 20000, ok no problem...
What if T=2000? Then pauseus = 0, ok not much of a problem...
What if T=2001? Then pauseus = 65526, ok, shouldn't happen because you've got T defined as a BYTE

But...what happens when you try to drive the servo out of it's physical limits?
What happens to the current draw if you hold a servo that's trying to move? Hook up an ammeter and find out real quick. And if you don't have an ammeter, hook up a voltmeter to your 'battery' and try it and see what happens to your voltage...

[burak450]

I think this part what you said....

Look at the loop in your code.
Aboslutely no 'bounds' checking.
What if...T = 0? Then pauseus = 20000, ok no problem...
What if T=2000? Then pauseus = 0, ok not much of a problem...
What if T=2001? Then pauseus = 65526, ok, shouldn't happen because you've got T defined as a BYTE

But...what happens when you try to drive the servo out of it's physical limits?
What happens to the current draw if you hold a servo that's trying to move? Hook up an ammeter and find out real quick. And if you don't have an ammeter, hook up a voltmeter to your 'battery' and try it and see what happens to your voltage...

[Acetronics2]

Hi Acetronics,
I think you are wrong because my signal is 50hz.
?

Lol ...

It has been verifyed with a R/C Pulsemeter.

Checks pulse AND repeating frequency ...

Y've done the mods to have your program running ...

Runs awfully bad for a tracker, but runs ... on the USB supply from my PC. ( 500 mA ! )

YOU are wrong in your calculations ... that's it !!!

[burak450]

Hi Acetronics,
First of all,calm down

I just said my idea...

I havent got R/C Pulsemeter,I cant measure the pulses...

Probably your calculations are right.I am here because my project doesnt work correctly and want to have second opinion.

Can you give me the right code ?

will only changing variable type byte to word be enough????

[skimask]

Can you give me the right code ?

will only changing variable type byte to word be enough????

Probably not...
Think about this...
How long does it take for ADCIN to execute?
How long does it take for LCDOUT to execute?
And fix your power supply...

[Acetronics2]

Hi, Burak

Don't worry for me ... I always am calm.

I Exceptionnaly cook code for others ...


so,

- you'll fist check "T" calculations and do not allow it to go out of the 800 - 2200 µs range

- Check for a "decent" increment to the same "T" variable

- Understand that 50 Hz is not a MUST ... just be in the 35-50 Hz range; doesn't need to be a constant frequ. nor.


PS: "Give me THE code" or "Give me THE scheme" are the sentences that suddently re activate my Altzheimer ...

What Were we talking about ??? ...

Alain