.define Mprint .sect .text .sect .rom .sect .data .sect .bss .sect .text ! This subroutine prints a zero terminated ascii string. ! The registerpair AX contains the start of the string. ! The subroutine WRCH is a special routine on the BBC microcomputer ! which prints the character in A to the screen. ! The subroutine WRCH is a special one provided by the BBC ! microcomputer. Mprint: stx ADDR ! start address of string (lowbyte) sta ADDR+1 ! start address of string (highbyte) ldy #0 1: lda (ADDR),y ! get ascii character beq 2f jsr WRCH ! put it on the screen iny bne 1b 2: rts