Atmega8 program

Hai Friends,

 4 days ago a man(Benson) came to my home. He asked if I can program in atmega .I programed in arduino Uno  not in atmega8 .But he said he is in a big problem. He is setting solar inverters for houses and offices. He had made a control unit. But there is problem in the program, battery is charging  Ac supply  when the battery has low power and low sun light .When this happens relay should cut for one minute and the on for one minute. Now battery is charging continuously. So for this change he tried to contact the person who designed the circuit and programed on atmega8.But he could not meet him. Even his family do not know where he is. Now Benson has 1000 boards .Enquiries are coming for solar project. So he requested me it will be great help to him if I solve this problem.

The following are my problem

1.Pin 9 connected to RS of LCD (1602A)and Pin 10 connect UTO how can i program in these pin. What is the code?

2.R/W is connected to pin 14 (Dig pin 8) R/W is connected to ground How can I change Dig pin8 to GND

3.He bought a arduino8 based board but my system can not install the drive for it. How can I install it


So if I  solve these problems that will be great help to that man


Are you using the arduino boot loader?

I believe the atmegga8  would be programmed using the “NG or Older” board type, if it is running the Arduino boot loader.  Are the atmegga8s in sockets or are they soldered in?

 Is there a programming header on the board? (6 or 10 pins near the MPU) If there is you can burn the boot loader to the atmegga8 then program using arduino. (Search for boot loader at   Or you can program the chip directly in C using Atmel Studio and a AVR programmer.

If there is no programming header and the chips are soldered in you can get clips that attach to the chip while its in place or you can always replace the chips with new ones. 

Pins 9 and 10 are PB6 and PB7.  That means the chip is using the internal oscillator and you might not be able to use the arduino boot loader.


I cant understand some of your questions.  What does UTO stand for?  If pin8 is not connected to ground its ether not a atmegga8 or using very unorthodox power connections.

Good luck and at least you will learn a lot trying to get these boards to work.


Re :RobotGoldfish

Thank you robotgoldfish,

Many informations are new to me.Thank you.He is programing in to the chip by Atmel Studio and a AVR programmer.A hex file was loaded in to the chip.Then the chip is replaced to the socket on the board.It is not UTO it is Auto/Manual is switch.In Auto mode battery discharge half then the other half if no supply.In Manual mode battery will discaharge fully. He bought the board arduino.So now understand that it can not use in this because boot loader is in it from your replay.This is the circuit diagram.