Originally Posted by fantasy1988

I click on the Fuse bits appear this image

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appear picture

All those fuse bits look good for using a ceramic resonator.

If you are using a quartz crystal then you should untick CKSEL0 and SUT0.

I load the hex file, check the circuit. ----> failure
version V 0.4 using atmega 8 ,LED always light (pin 25). But no signal pulse output (pin 13)
I use battery 2 s lipo , quazt crystal (setup fuse bit Ok )

I use program Prouteus simulation Atmega48 and Atmega8
result output Atmega48 have signal pulse (pin 13 ), led flash Ok
but output Atemega8 no signal output (pin 13 ) ,led flash
maybe I will order chip Atmega48 .hic hic

R1,R2 220Ohm, I think it very hot

Originally Posted by fantasy1988

R1,R2 220Ohm, I think it very hot

They have a low value to ensure that the signal is clean with a motor attached. You can use a much higher value (eg. 1k) in your circuit.

I use program Prouteus simulation Atmega48 and Atmega8
result output Atmega48 have signal pulse (pin 13 ), led flash Ok
but output Atemega8 no signal output (pin 13 ) ,led flash
maybe I will order chip Atmega48 .hic hic

Thanks for testing my ATmega8 code. As I suspected, it has a few bugs.

Please try this new version...

Bruce abbot,I check verison V0.5 with atmega8
I'm sorry, it still does not work . LED always light, (no flashing)
always have output pulse signal, I measured is 460ms., and have not any change when converting the PWM signal from the Fet
perhaps as you say, convert use atmga8 difficult , although I have a lot of chips atmega8 but I'll buy atmega 48 chip, and will make the new circuit
Okay,thanks a lot

Originally Posted by fantasy1988

Bruce abbot,I check verison V0.5 with atmega8
I'm sorry, it still does not work . LED always light, (no flashing)
always have output pulse signal, I measured is 460ms.

460uS is too low, it should never produce such a short output pulse. Perhaps your clock frequency is wrong?

I harvested an ATmega8 from an old ESC, but I couldn't think of an easy way to hook it up, so I bought a DIP version which I can plug into my breadboard. V0.5 firmware works fine with it, using a 16MHz ceramic resonator and fuse settings SUT1:0=10 CKSEL3:0=1110.

I did find a small bug that caused the LED to light with full brightness above 0% PWM input (it should only go to full brightness at 100% PWM). Here is V0.6, which fixes this bug.

Originally Posted by Bruce Abbott

V0.5 firmware works fine with it, using a 16MHz ceramic resonator and fuse settings SUT1:0=10 CKSEL3:0=1110.

.

thank you, I will try again.
maybe, I have some mistakes when set up fuse bit

I failure again
seems I'm not lucky, without any change.
can you show me some pictures of your circuit do (into breadboard)?
thanks

Originally Posted by fantasy1988

can you show me some pictures of your circuit do (into breadboard)?

The DIP version has different pinouts, so my breadboard layout probably won't help you much. I suggest that you carefully compare your layout to both the circuit in post #7 and the ATmega8 datasheet.

You appear to be using a quartz crystal. Do you have a 22pF capacitor from each leg of the crystal to ground? Capacitors may be required to make the crystal oscillate at the correct frequency (ceramic resonators don't need them because they have built-in capacitors).

Originally Posted by Bruce Abbott

The DIP version has different pinouts, so my breadboard layout probably won't help you much. .

yes, I will review the pinout of DIP and SMD

I just want to confirm the circuit has to work through your images.

I am yet use capactor 22 p, I will fix
 sure, I'll make it work

thanks again

bruce it worked, the only thing I have to say there was an issue with the schematic,the crystal pins did not match .they are wrong as far as the schematic did not work with the atmega 8. so what I had to do is build a schematic for atmega 8 , and connect the circuitry. do the programming
and that's it. it s few issues here and there but nothing really serious. thank you so much man.
sincerely

hey electrontube
are you use atmega48 ?

Attached is a pure analog circuit to generate the signal to control an ESC for a brushless motor. I use this circuit to control a brushless tail motor on an old FP helicopter. The brushless tail motor actually is too responsive and makes the heli more challenging to fly.

C3 can be made smaller to get faster response and the LM555 circuit can be changed to make the 20 mseconds between pulses shorter. As shown the circuit has almost no delay compared to the 20 msec between pulses.

This circuit has a small problem in that it requires at least 10 or 11 volts to operate. On my helicopter the 3S lipos would sag very fast to a lower voltage and the circuit would cut out. To fix the problem I added a small (150 mah) lipo in series with the main 3s battery to provide 16 volts instead of 12 volts. This battery could be even smaller like 80mah.

I suppose R8 could be a simple pair of resistors instead of a pot. I found the best setting is just about in the center so two 1K resistors would be about right.

The circuit is based on this circuit:
http://www.sentex.ca/~mec1995/gadgets/servo3.htm
I replaced the poteniometer P1 with a voltage derived from the PWM signal.