I'm in the process of shfiting a board using Atmel's atiny13 to the atiny25. The at25 is causing lots of trouble. First hassle was getting the at25 to accept the "program enable" command. There was no response. The data sheet states that an external clock signal is not required if the device is clocked by one of the internal oscillators. Presuming that the internal clock(s) was not connected, a 2mc signal was put on the clock input pin. Now the "program enable" command was accepted! The "write fuse" command looks proper and the at25 returns the anticipated data but the "read fuse" command returns a 0 - not matching what was written. The at25 appears to be fabricated by a different and newer process than the at13 which leaves lots of room for changes and errors. Anyone familar with the at25, or other devices made on the newer process, have any suggestions for getting this working?
Hul