atiny13 to atiny25

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

Reply to
Hul Tytus
Loading thread data ...

One of the protection bits set so that you can't read the fuses. Never had any problems with AT25 several years ago..

Reply to
TTman

I assume you are programming with 1-wire reset line. Never require external clock, but good clean programming clock/signal.

Yes, definitely try to clear the protection fuse.

Reply to
Ed Lee

but afaiu you can set the fuses so the internal clock is very slow and a programmer will only work when running very slow

Reply to
Lasse Langwadt Christensen

Yes, a good slow programmer would be good enough. I did program some AVR with another slow AVR.

Reply to
Ed Lee

Along the lines you suggest, I put the "chiperase" command first after the program enable command and the write fuse commands worked after that. The at25 isn't being programmed properly yet but it looks like the normal detail adjustment thats needed.

Hul

TTman snipped-for-privacy@gmail.com wrote:

Reply to
Hul Tytus

Ed, with your comment about a slow programmer in mind, I set a "go slow" option in this programmer. Just in case.

Hul

Ed Lee snipped-for-privacy@gmail.com wrote:

Reply to
Hul Tytus

Also credit Lasse for pointing it out first.

Reply to
Ed Lee

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.