>I have just developed an application for a PIC16c55. After checking
>if worked correctly I decided to blow it onto a OTP device for the
>final product. However, I got a fuse error report from the mps16b
>program. Exact details bellow:-
>
>Developement EPROM chip :   PIC16C55/JW-S1
>Final OTP chip          :   PIC16C55-XT/P
>
>Clocking method         :   8MHz Crystal
>
>I tried to program the OTP to use an HS clock. But it reported that
>it had been programmed LP !
>
>Is there something I don't know about these OTP chips. I thought they
>are supposed to be able to do everything the EPROM devices are.
>
>Could it simply be that this OTP chip is defective ?
>
>Anyone got any suggestions?
>
>Thanks,
>
>Wayne G Boyd.


 Wayne:
 The fuses on the 16c5x-xx otp series are indeed preprogrammed as to their
clocking method. (the only exception as far as I know is the -RC part).
 You are masking in the -HS fuse bit with the -XT bit and the result is -LP.
If you need the high speed chip, that is what you will have to order.

 Hope this helps.

carl

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Henry Carl Ott      N2RVQ
carlott@interport.net
http://www.interport.net/~carlott/
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