; ; Ullrich von Bassewitz, 05.08.1998 ; ; CC65 runtime: long sub ; ; ; EAX = TOS - EAX ; .export tossubeax .import addysp1 .importzp sp, sreg, tmp1, tmp2 tossubeax: ldy #0 sec sta tmp1 lda (sp),y sbc tmp1 ; byte 0 sta tmp2 ; use as temp storage iny stx tmp1 lda (sp),y sbc tmp1 ; byte 1 tax iny lda (sp),y sbc sreg ; byte 2 sta sreg iny lda (sp),y sbc sreg+1 ; byte 3 sta sreg+1 lda tmp2 ; load byte 0 jmp addysp1 ; drop TOS