servo motor resets 16f877a

[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

[burak450]

Ok.I wont want you to give code because i know Altzheimer is very tough disease

I am gonna try what you said.If I fail I will disturb you again

Thanks for help up to now....

[Macgman2000]

Why not just write simple code to sweep servo left to right and back right to left for testing? BTW, if you use a 5v regulator with 5v output power supply, it will cause a power drop when you try to draw current. A voltage reg will probably need 6.5v++ input voltage. Also, I have driven 4 large servos off of 2 paralleled voltage regs and a low current reg for the pic....no problems at all.

[Acetronics2]

Hi, Burak

We haven't solved the power problem ...

so, I ask the question once more : Which is your testboard ???

Alain

[burak450]

Macgman2000 wants my code...

I wrote a new code to protect values which makes out of range.

DEFINE LCD_DREG PORTB
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTB
DEFINE LCD_RSBIT 4
DEFINE LCD_EREG PORTB
DEFINE LCD_EBIT 5
DEFINE LCD_BITS  4
DEFINE LCD_LINES 2
DEFINE OSC 4                                                                       
DEFINE ADC_BITS     8      
DEFINE ADC_CLOCK  3       
DEFINE ADC_SAMPLEUS 100
SYMBOL F=PORTA.0
SYMBOL G=PORTA.1
alta var byte
usta var byte
altb var byte
ustb var byte
ADCON1=2
TRISA=3
TRISB=0
PORTB=0
TRISC=0
LCDOUT $FE,1 
pause 4000
adcin  0,ALTa
ADCin  1,usta

t var byte
i var byte
T=150

yap:




adcin  0,altb
ADCin  1,ustb






if  ((((usta+10)*100)/(ustb+10)))>130 and (not (t>194)) then 
T=T+15
endif

if (((alta*100)/altb))>130 AND (not (t<51)) then 
T=T-15
endif


gosub motor





  

LCDOUT $fe,2,#usta," ",#ustb," ",#altA," ",#altb
lcdOUT $fe,$C0,#T   

goto yap

motor:
for i=0 to 25
PULSOUT PORTC.2,T
PAUSEUS 20000-(T*10)
next
return

end

I am using breadboards.A minute ago i tried to connect two parallel power supply.Servo didnt reset MCU.I was glad but sometimes when i turned power on ,servo turned full left sometimes didnt.I think my servos are crazy .BTW I connected a capacitor.

I have an idea.Can this error(full left error) occur because of my code that i wrote.too many PAUSEUS may make this error.Should I try DUTYCYLE or PWM codes???

Or Is there any power problem???

[Macgman2000]

If you have an oscilloscope look at your control pulses from the PIC to the servo as it moves. If you see that the wave form (1~2ms pulse) is wiggling around or changing amplitude then you have a power supply issue. Do as I suggested above, get a 9v power supply (AC/DC) and use TWO 7805 regulators in parallel for the servo ONLY. At the servo use 470uF across power and ground. Look at the scope again and make sure you see a "cleaned" up signal while servo is in motion.

Nick

[burak450]

If you have an oscilloscope look at your control pulses from the PIC to the servo as it moves. If you see that the wave form (1~2ms pulse) is wiggling around or changing amplitude then you have a power supply issue. Do as I suggested above, get a 9v power supply (AC/DC) and use TWO 7805 regulators in parallel for the servo ONLY. At the servo use 470uF across power and ground. Look at the scope again and make sure you see a "cleaned" up signal while servo is in motion.

Nick

I tried everything which is suggested.I changed code and put PAUSEUS before pulsout.Something wrong ,I got same error I decided to change power supply.That can cause this problem.

I hope it will solve my problem...

I will use two servos...(one for left-right one for up-down).I wrote the code just for left-right.I will make servos TWO if I am successful left-right position...

Why did you say two parallel 7805? One for pic and one for servo?

How many 7805 regulators should I use?

[skimask]

I wrote a new code to protect values which makes out of range.

In the middle of that math mess? I don't think it's a good spot for it...but that's just me...

DEFINE LCD_DREG PORTB
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTB
DEFINE LCD_RSBIT 4
DEFINE LCD_EREG PORTB
DEFINE LCD_EBIT 5
DEFINE LCD_BITS  4
DEFINE LCD_LINES 2
DEFINE OSC 4                                                                       
DEFINE ADC_BITS     8      
DEFINE ADC_CLOCK  3       
DEFINE ADC_SAMPLEUS 100
f var porta.0 : g var porta.1 : alta var byte : usta var byte : altb var byte
ustb var byte : t var byte : i var byt e: adcon1=2 : trisa=3 : trisb=0
portb=0 : trisc=0 : pause 1000 : lcdout $fe,1 : pause 4000
adcin  0,ALTa : ADCin  1,usta : t=150
pulsout portc.2,t 'initial servo kick to center
yap: adcin 0,altb : adcin 1,ustb
if ((((usta+10)*100)/(ustb+10)))>130 and (not (t>194)) then T=T+15
if (((alta*100)/altb))>130 AND (not (t<51)) then T=T-15
'bounds checking...
if t < 100 then t=100
if t > 200 then t=200
'bounds checking
'if 100 isn't low enough, change it, if 200 isn't high enough, change it
gosub motor : lcdout $fe,2,#usta," ",#ustb," ",#altA," ",#altb, $fe,$C0,#T
goto yap
motor: for i=0 to 25 : PULSOUT PORTC.2,T : PAUSEUS 20000-(T*10) : next i
return
end

[Acetronics2]

but sometimes when i turned power on ,servo turned full left sometimes didnt.I think my servos are crazy .BTW I connected a capacitor.

I have an idea.Can this error(full left error) occur because of my code that i wrote.too many PAUSEUS may make this error.Should I try DUTYCYLE or PWM codes???

Or Is there any power problem???

Always Place a:

LOW PORTx.y

just before the PULSIN command ...

That's all !

Alain

[skimask]

Always Place a:
LOW PORTx.y
just before the PULSIN command ...

I've heard you say that a number of times...not bad advice by any stretch...but I'm wondering why I've never had to use it and others seem to have so much trouble with that particular 'gotcha'...

[burak450]

A voltage reg will probably need 6.5v++ input voltage. Also, I have driven 4 large servos off of 2 paralleled voltage regs and a low current reg for the pic....no problems at all.

A low current reg?

He said we used large servos and mine is not large but I have to ask it because after a hour i will go to buy (9v supply,7805..,)

Should I buy a current regulator?

[mackrackit]

No current regulator.
What he means is say one 7805 will run the PIC (7805 at best 1 amp) = low current.

Power supply for motors are made from parallel 7805s or some other type to handle the amperage needed.

[burak450]

No current regulator.
What he means is say one 7805 will run the PIC (7805 at best 1 amp) = low current.

Power supply for motors are made from parallel 7805s or some other type to handle the amperage needed.

thanks a lot i am gonna try it...

hi Acetronics ,

I am sure i changed code like that

motor:
for i=0 to 25
PAUSEUS 20000-(T*10)
PULSOUT PORTC.2,T

next
return

[burak450]

God bless you guys!

1-I connected 9v 450ma(I hope 450ma is fine) power supply and connected two 7805 paralel and used a 470uf between vdd and vss.Mcu doesnt reset itself and works fine! But I think servo works a little bit slower than past.I dont know why? maybe changing power supply from 5.2 to 5 makes this difference...If its neccessary I can put here its video...

2-I think I finished left-right position and wrote a new code to complete my project.I wrote this
but That doesnt work and servo2(up-down) made some stupid moves (like vibration).Also left-right motion gets very very slower...I know I made too many mistakes.But I learned here this forum too many things that I dont know.Everybody wants to help here and I was a little suprised at the beginning of this Thread.I put my code here.

Can you help me again? t for left-right j for up-down.I bounded "j" between 135 and 115

My code is....

DEFINE LCD_DREG PORTB
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTB
DEFINE LCD_RSBIT 4
DEFINE LCD_EREG PORTB
DEFINE LCD_EBIT 5
DEFINE LCD_BITS  4
DEFINE LCD_LINES 2
DEFINE OSC 4                                                                       
DEFINE ADC_BITS     8       'A/D çevirim sonucu kaç bit olacak
DEFINE ADC_CLOCK  3       'Clock kaynağı (3=rc)
DEFINE ADC_SAMPLEUS 100
SYMBOL F=PORTA.0
SYMBOL G=PORTA.1
alta var byte
usta var byte
altb var byte
ustb var byte
sola var byte
solb var byte
saga var byte
sagb var byte
k var byte
t var byte
i var byte
j var byte
ADCON1=2
TRISA=%00001111 
TRISB=0
PORTB=0
TRISC=0
LCDOUT $FE,1 
pause 2000
adcin  0,ALTa
ADCin  1,usta
adcin  2,sola
adcin  3,saga

T=150
j=125
yap:




adcin  0,altb
ADCin  1,ustb
adcin  2,solb
adcin  3,sagb






if  ((((usta+10)*100)/(ustb+10)))>130 and (not (t>194)) then 
T=T+15
endif

if (((alta*100)/altb))>130 AND (not (t<51)) then 
T=T-15
endif

if  ((((sola+10)*100)/(solb+10)))>130 and (not (t>134))    then 
j=j+10
endif

if (((saga*100)/sagb))>130 AND (not (j<116)) then 
j=j-10
endif

gosub motor2
gosub motor1






  

LCDOUT $fe,2,#usta," ",#ustb," ",#altA," ",#altb
lcdOUT $fe,$C0,#T,"  ",#j    

goto yap

motor1:
for i=0 to 25
PAUSEUS 20000-(T*10)
PULSOUT PORTC.2,T

next
return

motor2:
for k=0 to 25
PAUSEUS 20000-(j*10)
PULSOUT PORTC.3,j

next
return

end