Monitor error 26: Cannot write interrupt vector on ADuC812

Hi!

I have the problem with stopping program execution on serial interrupt with mon51.

When I check option 'Stop program execution on serial interrupt' I get 'Monitor error 26: Cannot write interrupt vector'.

I have set everything options as it was written in application note No 151.

I'm not sure if monitor writes something at address 0x23 in code memory (which is impossible on AduC812 since it has Flash memory from 0x0000 to 0x2000), or it writes at 0x2023 (I have interrupt vector table from adress 0x2000 in RAM).

Statement

char code reserve [3] _at_ 0x23;

char code reserve [3] _at_ 0x2023;