millfork/include/x16_hardware.mfk

// TODO: bankswitching


volatile byte vera_addr_hi @ $9f20
volatile byte vera_addr_mi @ $9f21
volatile byte vera_addr_lo @ $9f22
volatile byte vera_data1 @ $9f23
volatile byte vera_data2 @ $9f24
volatile byte vera_ctrl @ $9f25
volatile byte vera_ien @ $9f26
volatile byte vera_isr @ $9f27

struct vera_layer_setup {
    byte ctrl0
    byte ctrl1
    word map_base
    word tile_base
    word hscroll
    word vscroll
}

asm void set_vera_layer_internal(pointer.vera_layer_setup ax, byte y) {
    sta __reg
    stx __reg+1
    stz vera_ctrl
    lda $14
    sta vera_addr_hi
    stz vera_addr_mi
    sty vera_addr_lo
    ldy #0
    __set_layer_internal_loop:
    lda (__reg),y
    sta vera_data1
    iny
    cpy #sizeof(vera_layer_setup)
    bne __set_layer_internal_loop
    ? rts
}

asm void set_vera_layer0(pointer.vera_layer_setup ax) {
    ? ldy #0
    ? jmp set_vera_layer_internal
}

asm void set_vera_layer1(pointer.vera_layer_setup ax) {
    ? ldy #0
    ? jmp set_vera_layer_internal
}

inline void vera_poke(int24 address, byte value) {
    vera_addr_lo = address.b0
    vera_addr_mi = address.b1
    vera_addr_hi = address.b2
    vera_ctrl = 0
    vera_data1 = value
}

inline void vera_fill(int24 address, byte value, word size) {
    word i
    vera_addr_lo = address.b0
    vera_addr_mi = address.b1
    vera_addr_hi = address.b2 | $10
    vera_ctrl = 0
    for i,0,paralleluntil,size {
        vera_data1 = value
    }
}

void vera_upload_large(int24 address, pointer source, word size) {
    word i
    vera_ctrl = 0
    vera_addr_lo = address.b0
    vera_addr_mi = address.b1
    vera_addr_hi = address.b2 | $10
    for i,0,paralleluntil,size {
        vera_data1 = source[i]
    }
}

inline void vera_upload(int24 address, pointer source, byte size) {
    byte i
    vera_ctrl = 0
    vera_addr_lo = address.b0
    vera_addr_mi = address.b1
    vera_addr_hi = address.b2 | $10
    asm {
        ? ldy #0
        __vera_upload_loop:
        ? lda (__reg),y
        ? sta vera_data1
        ? iny
        ? cpy size
        ? bne __vera_upload_loop
    }
}

struct vera_sprite_data {
    word address
    word x
    word y
    byte ctrl0
    byte ctrl1
}