ClearBuffer:
    xor a
FillBuffer:
    push de
    push bc
        ld d,a
        ld e,a
        call SafeInterruptDI
        push af
        ld (saveSP),sp
        ld sp,LCDBuffer+768
        ld b,32
_           push de
            push de
            push de
            push de
            push de
            push de
            push de
            push de
            push de
            push de
            push de
            push de
            djnz -_
        ld sp,(saveSP)
    pop af
    pop bc
    pop de
        ret c
    ei
    ret
SafeInterruptDI:
    xor a       ;Set nc (interrupts)

    out ($20),a     ;Set speed to slow

    push    af      ;Check interrupts

    pop af

    ld  a,i     ;pe if interrupt

    di

        ret pe      ;Return if interrupts on

    dec sp      ;Otherwise, robust test

    dec sp

    pop af

    or  a       ;Set nc (interrupts)

        ret nz      ;Return if interrupts on

    scf         ;Set c (no interrupts)

    ret         ;Return
; safely returns interrupts
; inputs    af = state flags
SafeInterruptEI:
    ret c
    ei
    ret