add datetime device, revise device handling, remove tracing code

lib/Varvara/Datetime.ml

@@ -0,0 +1,34 @@
+module Make () : Uxn.Device.DEVICE with type state = unit = struct
+  type state = unit
+
+  let state = ()
+
+  let dei_ports =
+    Uxn.Device.Int_set.of_list
+      [ 0xc0; 0xc2; 0xc3; 0xc4; 0xc5; 0xc6; 0xc7; 0xc8; 0xca ]
+
+  let deo_ports = Uxn.Device.Int_set.empty
+
+  let dei _ port =
+    let now = Unix.time () in
+    let tm = Unix.localtime now in
+    match port with
+    | 0xc2 -> tm.Unix.tm_mon
+    | 0xc3 -> tm.Unix.tm_mday
+    | 0xc4 -> tm.Unix.tm_hour
+    | 0xc5 -> tm.Unix.tm_min
+    | 0xc6 -> tm.Unix.tm_sec
+    | 0xc7 -> tm.Unix.tm_wday
+    | 0xca -> Bool.to_int tm.Unix.tm_isdst
+    | _ -> assert false
+
+  let dei2 _ port =
+    let now = Unix.time () in
+    let tm = Unix.localtime now in
+    match port with
+    | 0xc0 -> tm.Unix.tm_year + 1900
+    | 0xc8 -> tm.Unix.tm_yday
+    | _ -> assert false
+
+  let deo _ _ _ = assert false
+end