Preserving 18F47Q84 USER ID Memory using ICD-U80 / CCSLoad

[JamesW]

Can anyone offer a bit of help please?

We've got a new product where we are storing some key product information in USER ID MEMORY (0x200000 - 0x20001F) on the PIC18F47Q84-I/PT. (Such things as unit serial number, and some user settings).

Whilst CCSload will let you protect Data EE memory to prevent it be over-written during programming/verification, there doesn't seem to be an obvious option to prevent the serial number being overwritten if the code on the unit needs to be updated.

We can do it with MPLAB IPE, but only have one of them and 5 ICD-U80's

Any ideas?

Thanks in advance

James

[Ttelmah]

Disable the option to force a full erase, and untick the selection for the
configuration fuses. The ID is part of the configuration area. You can't
preserve this if you make any changes to the fuses,

[JamesW]

Thanks for that - did think there must be a way of doing it.

What do I do about writing the fuse settings to the device initially? I assume that when I write the serial numbers, I must set the fuses at the same time?

James