Motorolla MC 68HC705J5A programming problems

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my company bought the 68HC705J5 as a replacement of the 68HC705J1 and
I'm having problems programming this microcontroller. That this
controller is only a OTP of course doesnt make things easier :-(

I'm using the Motorola M68HC705UPGMR Programmer for programming. This
programmer loads the .bin file that I transfered to an 27C256 EPROM from
that EPROM into the microcontrollers user EPROM. As far as I understood
from the programmers manual, the programcode in the EPROM has to begin
at the same address as the internal EPROM of the microcontroller does.
(which is $300 for this device) - so now the code in my EPROM starts in
$300, prior of that address are only FFs. I can load the data into the
microcontroller and even verify it - but the microcontroller refuses to
work properly. The program-code is the same code that was used for the
68HC705J1, but I of course changed the InterruptVector addresses and the
register settings according to the changes that were made between the
two processors. I cant see why the code does not work in the "new"

Is there someone out there who had a similar problem and can help me to
solve it?


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