how to implement an own flashing-software for an ATmega8-microcontroller

has anyone some kind of documentation how to implement an own flashing-procedure for an atmega8-microcontroller ?

when searching, i have only found tutorials, on how to flash custom software with the normal flashing-software (in most cases atmels flip), but i haven´t found any documentation, how you would implement it in your own software. eg. what are the commands in which timings and with which 开发者_Python百科responses from the microcontroller.

so, thank you in advance

You program the chip by communicating with it through SPI lines while it is in reset. You can find details in the chip's datasheet.

You can't do that directly from your PC, you need to have an external hardware device (even if it is a mere level converter connected to your serial/parallel port). How you communicate with that device depends on the device.

If you want to implement bootloader functionality, you should take a look at boot_page_write() function in avr-gcc help. Basically what you need is the data stream from PC/other uC which will accumulate in RAM until you have enough to write one page.

You can search for AVR Universal Boot loader for example how it can be implemented.