C51: The file order in the project causes errors.

do you have any code that specifies location?

do you have any code that specifies location?

Can you tell us if you have any code in your project that specifies location?

Yes, there is a code that reserve space in memory, set CRC value and flash protection.

CSEG AT 17FEh
ProgCRC: DW 4D67h

// conf memory
CSEG AT 1800h
ConfMem: DS 1024

CSEG AT 1DFFh
FlashProtection: DB (~(12))     // First 6KB locked -> 12 pages, 512B each

CSEG AT 1E00h
ReservedFlash: DS 512           // last page of flash

END

The above code is located in separate .a51 file that is linked as last file, in the configuration which behave correct (where Startup.a51 file is linked as first).

which chip?

I would be inclined to take a close look at the map files and in particular check the differences between working and failing.

Zeusti

It's a Silicon Labs C8051F353.

15.1.1. Flash Lock and Key Functions
Flash writes and erases by user software are protected with a lock and key function. The Flash Lock and Key Register (FLKEY) must be written with the correct key codes, in sequence, before Flash operations may be performed. The key codes are: 0xA5, 0xF1. The timing does not matter, but the codes must be written in order. If the key codes are written out of order, or the wrong codes are written, Flash writes and erases will be disabled until the next system reset. Flash writes and erases will also be disabled if a Flash write or erase is attempted before the key codes have been written properly. The Flash lock resets after each write or erase; the key codes must be written again before a

so, when

CSEG AT 1DFFh
FlashProtection: DB (~(12))     // First 6KB locked -> 12 pages, 512B each

get written, to memory you are hosed as far as writing the rest of your code