User input test

!to "disk_32e5370fc2358b90.img"
*=0x500

    SEC
    XCE
    REP #$30        ; 16-bit mode
    !al

    LDA #$1
    MMU #$0         ; map device 1 to redbus window
    LDA #$300
    MMU #$1         ; redbus window situated at 0x300
    MMU #$2         ; enable redbus

    LDA #$400
    MMU #$3         ; external memory situated at 0x400
    MMU #$4         ; enable external memory

    LDA #$500
    MMU #$6         ; POR = 0x500, whatever that might be

    LDA #$0
    STA $303        ; hide cursor

    SEP #$30        ; 8-bit mode
    !as

    LDX #$0         ; position to write to

--  LDY $305        ; keys in buffer
    CPY #$0
    BEQ --

-   CPY $304
    BEQ +
    LDA $306        ; the key
    STA $310,X
    INC $304
    INX
    JMP -

+   LDA #$0
    STA $305
    STA $304
    JMP --
    WAI

!align 128, 128, 0