reorganization and project rename

lib/kestrel_varvara/System.ml

@@ -0,0 +1,107 @@
+open Kestrel
+
+type state = { banks : bytes array }
+
+module Make () : Kestrel.Device.DEVICE with type state = state = struct
+  type nonrec state = state
+
+  let state = { banks = Array.init 15 (fun _ -> Bytes.create 65536) }
+  let dei_ports = Kestrel.Device.Int_set.of_list [ 0x04; 0x05 ]
+
+  let deo_ports =
+    Kestrel.Device.Int_set.of_list [ 0x02; 0x04; 0x05; 0x0e; 0x0f ]
+
+  let print_stack ~name (Kestrel.Machine.Stack { data; sp }) =
+    Printf.eprintf "%s " name;
+    for i = sp - 8 to sp - 1 do
+      Printf.eprintf "%02x%s"
+        (Bytes.get_uint8 data (i land 0xff))
+        (if i land 0xff == 0xff then "|" else " ")
+    done;
+    Printf.eprintf "<%02x\n" sp
+
+  let get_bank mach bank =
+    if bank = 0 then Machine.ram mach
+    else if bank > 0 && bank < 16 then state.banks.(bank - 1)
+    else Bytes.create 0
+
+  let expansion mach cmd_addr =
+    let ram = Machine.ram mach in
+    let cmd = Bytes.get_uint8 ram cmd_addr in
+    match cmd with
+    | 0x00 ->
+        let length = Util.get_uint16_wrap ~wrap:0xffff ram (cmd_addr + 1) in
+        let bank = Bytes.get_uint16_be ram (cmd_addr + 3) in
+        let addr = Util.get_uint16_wrap ~wrap:0xffff ram (cmd_addr + 5) in
+        let value = Bytes.get_uint8 ram (cmd_addr + 7) in
+        if bank < 16 then begin
+          let mem = get_bank mach bank in
+          for i = 0 to length - 1 do
+            let pos = (addr + i) land 0xffff in
+            Bytes.set_uint8 mem pos value
+          done
+        end
+    | 0x01 ->
+        let length = Util.get_uint16_wrap ~wrap:0xffff ram (cmd_addr + 1) in
+        let src_bank = Bytes.get_uint16_be ram (cmd_addr + 3) in
+        let src_addr = Util.get_uint16_wrap ~wrap:0xffff ram (cmd_addr + 5) in
+        let dst_bank = Bytes.get_uint16_be ram (cmd_addr + 7) in
+        let dst_addr = Util.get_uint16_wrap ~wrap:0xffff ram (cmd_addr + 9) in
+        if src_bank < 16 && dst_bank < 16 then begin
+          let src_mem = get_bank mach src_bank in
+          let dst_mem = get_bank mach dst_bank in
+          for i = 0 to length - 1 do
+            let src_pos = (src_addr + i) land 0xffff in
+            let dst_pos = (dst_addr + i) land 0xffff in
+            let v = Bytes.get_uint8 src_mem src_pos in
+            Bytes.set_uint8 dst_mem dst_pos v
+          done
+        end
+    | 0x02 ->
+        let length = Util.get_uint16_wrap ~wrap:0xffff ram (cmd_addr + 1) in
+        let src_bank = Bytes.get_uint16_be ram (cmd_addr + 3) in
+        let src_addr = Util.get_uint16_wrap ~wrap:0xffff ram (cmd_addr + 5) in
+        let dst_bank = Bytes.get_uint16_be ram (cmd_addr + 7) in
+        let dst_addr = Util.get_uint16_wrap ~wrap:0xffff ram (cmd_addr + 9) in
+        if src_bank < 16 && dst_bank < 16 then begin
+          let src_mem = get_bank mach src_bank in
+          let dst_mem = get_bank mach dst_bank in
+          for i = length - 1 downto 0 do
+            let src_pos = (src_addr + i) land 0xffff in
+            let dst_pos = (dst_addr + i) land 0xffff in
+            let v = Bytes.get_uint8 src_mem src_pos in
+            Bytes.set_uint8 dst_mem dst_pos v
+          done
+        end
+    | _ -> Format.eprintf "System/expansion: unknown command #%02x" cmd
+
+  let dei m port =
+    match port with
+    | 0x04 ->
+        let (Machine.Stack { sp; _ }) = Machine.wst m in
+        sp
+    | 0x05 ->
+        let (Machine.Stack { sp; _ }) = Machine.rst m in
+        sp
+    | _ -> assert false
+
+  let dei2 _ _ = assert false
+
+  let deo mach port value =
+    match port with
+    | 0x02 -> expansion mach value
+    | 0x04 ->
+        let (Machine.Stack s) = Machine.wst mach in
+        s.sp <- value land 0xff
+    | 0x05 ->
+        let (Machine.Stack s) = Machine.rst mach in
+        s.sp <- value land 0xff
+    | 0x0e ->
+        if value <> 0 then begin
+          print_stack ~name:"wst" (Machine.wst mach);
+          print_stack ~name:"rst" (Machine.rst mach);
+          Out_channel.flush stderr
+        end
+    | 0x0f -> Bytes.set_uint8 (Machine.dev mach) 0x0f value
+    | _ -> assert false
+end