; ix = this
; f <- c: found
Franky_Detect:
    xor a
    out (40H),a  ; make sure no known switched I/O device is listening
    di
    ld a,0C0h
    ld b,081h
    call WR_VDP_Franky      ; MASK Franky VDP IRQ
    ld a,007h
    ld b,080h
    call WR_VDP_Franky      ; Set Franky VDP into M4 mode, EXTVID active
    in a,(89h)
    in a,(89h)
    and 060h
    ret nz
    in a,(48h)
    cp 0D5h
    ret nz
    ld a,006h
    ld b,080h
    call WR_VDP_Franky      ; Disable Franky VDP EXTVID mode
    ei
    scf
    ret

WR_VDP_Franky:
    out (89h),a
    ld a,b
    out (89h),a
    ret