added z80.retryInterrupts to support astrocade IRQ retry mode

doc/notes.txt

@@ -156,7 +156,7 @@ TODO:
   - switching platform of a repo?
   - make sure to flatten subdirs
 - astrocade
-  - EI should trigger interrupt if pending? (see stash, might need z80 option)
+  - what if update earlier part of screen with different palette? it'd be nice to have instant updates when debugging tho...
 - ctrl+alt+l on ubuntu locks screen
 
 WEB WORKER FORMAT

src/platform/astrocade.ts

@@ -381,7 +381,7 @@ const _BallyAstrocadePlatform = function(mainElement, arcade) {
       }
       // interrupt
       if (sl == inlin && (inmod & 0x8)) {
-        // TODO: interrupt mode bit 0x4
+        cpu.retryInterrupts = !(inmod & 0x4);
         cpu.requestInterrupt(infbk);
       }
       // refresh this line in frame buffer?

src/platform/sms.ts

@@ -41,12 +41,12 @@ var SG1000_KEYCODE_MAP = makeKeycodeMap([
   [Keys.B,     0, 0x20],
 
   [Keys.P2_UP,    0, 0x40],
-  [Keys.A,        0, 0x80],
-  [Keys.P2_RIGHT, 1, 0x1],
-  [Keys.B,        1, 0x2],
-  [Keys.P2_LEFT,  1, 0x4],
-  [Keys.P2_DOWN,  1, 0x8],
-  [Keys.START,    1, 0x10],
+  [Keys.P2_DOWN,  0, 0x80],
+  [Keys.P2_LEFT,  1, 0x1],
+  [Keys.P2_RIGHT, 1, 0x2],
+  [Keys.P2_A,     1, 0x4],
+  [Keys.P2_B,     1, 0x8],
+  [Keys.VK_BACK_SLASH,    1, 0x10], // reset
 ]);
 
 class SG1000Platform extends BasicZ80ScanlinePlatform implements Platform {