[SOLVED] problem in writing FLASH memory of AVR via ISP

vinodstanur said:

when I am tying to write and read the FLASH, I am always gettign 0xff while reading,,,

I used command 60,68 to write and 20,28 to read (lower byte and higher byte respectively)

Click to expand...

In some devices, there is no method to detect when the Flash write cycle has ended. For this
reason, the programmer presented in this application note waits N ms before attempting to send
another command to the interface (the delay N will depend on target device, and can be found in
the programming section of the datasheet). For some devices it is possible to use polling. When
a byte is being programmed into the Flash or EEPROM, reading the addressed location being
programmed will give a value M (often $FF). At the time the device is ready for a new byte, the
programmed value will read correctly. This can be used to determine when the next byte can be
written. When programming the value M polling will not work, and a delay N should be used
before writing the next value. Polled mode will decrease the time required to program a device

Click to expand...

The Flash is programmed one page at a time.

Click to expand...

vinodstanur said:

I conudn't understand how we write flash by one page at a time..
More over, I think it is not explained in data sheet and the ISP application note..

Click to expand...