I need select drive without error message (must return only error code). In basic is this impossible, ok. I write small routine in assembler:

Код:
                ld      a, b            ;A = drive number
                ld      c, 1            ;C = service number 1 = select drive
                ei
                call    3D13h           ;call tr-dos service
But if diskette in selected drive not exist then tr-dos show error message "Retry,Abort,Ignore"... with possibility return to basic after press "A" :-(

Can anyone write correct routine for me ?