AVR Fuse Bits setting with Sinaprog

[alexan_e]

I haven't used power saving modes but if you use the mcu within specs then it can work 24/7 without a problem.
I guess there is something else wrong too or this is some code error.

 

[A.Rashad]

I haven't used power saving modes but if you use the mcu within specs then it can work 24/7 without a problem.
I guess there is something else wrong too or this is some code error.

The code was posted as attached document

 

[alexan_e]

You circuit includes relays so is it possible that switching creates a problem with the mcu power supply?
Have you placed diode across the relay?
Is the relay supply from a separate power supply that the mcu (not the same 5v regulator)?
Have you tried removing the relays and check if the circuit works with leds in place of the replays (so that there is no case or relay interference with the mcu)?

 

[A.Rashad]

You circuit includes relays so is it possible that switching creates a problem with the mcu power supply?
Have you placed diode across the relay?
Is the relay supply from a separate power supply that the mcu (not the same 5v regulator)?
Have you tried removing the relays and check if the circuit works with leds in place of the replays (so that there is no case or relay interference with the mcu)?

Hello,

Yes I have connected free wheeling diode across all four relays in reverse position(cathode to negative of coil, Anode to Positive 12V of coil)
I have used ULN2003 at output port of ATmega8 ,
But the power source is same for relays as well as for ATMEGA , I will check as you described by taking out relays ...
Thank you very much for support...

 

[alexan_e]

You mean you use the output from the 5v mcu regulator for the relays?
Is so try to supply the relays from before the regulator (assuming that the voltage is ok for the relays and not too high)

 

[A.Rashad]

You mean you use the output from the 5v mcu regulator for the relays?
Is so try to supply the relays from before the regulator (assuming that the voltage is ok for the relays and not too high)

Hello,
No no , actually I am taking 12V for relays, from input of MCU regulator only, Not from the output of regulator.
Output of 1117(5V ) is going only to MCU .
Yesterday I cheked my design by removing the relays from PCB , its working fine for four LEDs, the problem may be same with power supply, I am designing new PCB where I will separate both supply , I will design On board SMPS which will give 12 and 5 V ,
will this design be Ok ? Or Should I use two different SMPS one for 12V one for 5V , In this case , if I short Ground(necessary for operation) , will there be again issue of switching Interference ?

 

[alexan_e]

I'm not sure what to suggest, normally if the supply decoupling is good enough there is no problem.
Do search for led interference , you will find a few threads about that subject.