gpu.clj

(defn read-8 [emu addr]
  (println "gpu read at" (binary/int->hex-string addr))
  (cond
    (and (<= 0x8000 addr) (<= addr 0x9fff))
    (.getUint8 (-> emu :gpu :vram) addr)

    ; TODO: Read CTRL.
    (= 0xff40 addr) 0

    ; TODO: Read status.
    (= 0xff41 addr) 0

    ; TODO: Read scy.
    (= 0xff42 addr) 0

    ; TODO: Read scx.
    (= 0xff43 addr) 0

    ; TODO: Read ly.
    (= 0xff44 addr) 0

    ; TODO: Read lyc.
    (= 0xff45 addr) 0

    (= 0xff46 addr)
    (throw (ex-info "Unreachable GPU read: DMA request" {:addr (binary/int->hex-string addr)}))

    ; TODO: Read BG palette.
    (= 0xff47 addr) 0

    ; TODO: Read object palette 0.
    (= 0xff48 addr) 0

    ; TODO: Read object palette 1.
    (= 0xff49 addr) 0

    ; TODO: Read wy.
    (= 0xff4a addr) 0

    ; TODO: Read wx.
    (= 0xff4b addr) 0

    ; TODO: Read vram_select.
    (= 0xff4f addr) 0

    ; TODO: Read HDMA src_high.
    (= 0xff51 addr) 0

    ; TODO: Read HDMA src_low.
    (= 0xff52 addr) 0

    ; TODO: Read HDMA dest_high.
    (= 0xff53 addr) 0

    ; TODO: Read HDMA dest_low.
    (= 0xff54 addr) 0

    :else
    (throw (ex-info "Unsupported GPU register read" {:addr (binary/int->hex-string addr)}))))