This list is a defacto Atmel list as well now so  -

We developed an Atmel programmer for the above 1051, 2051 & 4051. We
used chips with batch numbers 9719 9716 9631. They were OK.

We are now about to release the programmer but chips with batch number
9836 have a problem programming. Byte verification fails at a byte early
on. But if one verifies the complete burn then the verification is OK.
We have just found this problem. Can anyone suggest anything?

Many thanks,

peter crowcroft
peter@kitsrus.com
http://kitsrus.com.