title History main tool name ('HIST') ; Program must hold the RSX HISTRSX1 - it installs or removes the RSX OS equ 0000h BDOS equ 0005h .string equ 9 .RSX equ 60 RSX_Oxx equ 55 lf equ 0ah cr equ 0dh eot equ '$' ld de,$SCBPB ld c,.RSX call BDOS ; Simple call or a ; Test success jp z,OS ; Yeap ld de,$RSXMSG ld c,.string ; Else tell error jp BDOS ; $RSXMSG: db cr,lf,'History RSX not found',eot $SCBPB: db RSX_Oxx end