Halt Z80 on SYS_reset() / SYS_hardReset()

Stephane-D · Dec 15, 2024 · 617e3cb · 617e3cb
1 parent 1fcfb6f
commit 617e3cb
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Showing 2 changed files with 14 additions and 4 deletions.
diff --git a/lib/libmd.a b/lib/libmd.a
diff --git a/src/sys_a.s b/src/sys_a.s
@@ -7,22 +7,32 @@ func SYS_assertReset
 
 
 func SYS_reset
-    move   #0x2700,%sr
-    move.l (0),%a7
+    move    #0x2700,%sr
+    move.l  (0),%a7
 
     move    %sp, %usp
     sub     #USER_STACK_LENGTH, %sp         // configure a USER_STACK_LENGTH bytes user stack at bottom, and system stack on top of it
 
+    move.l  #0xA11100,%a0       /* Z80_HALT_PORT */
+    move.w  #0x0100,%d0
+    move.w  %d0,(%a0)           /* HALT Z80 */
+    move.w  %d0,0x0100(%a0)     /* END RESET Z80 */
+
     jmp     _reset_entry
 
 
 func SYS_hardReset
-    move   #0x2700,%sr
-    move.l (0),%a7
+    move    #0x2700,%sr
+    move.l  (0),%a7
 
     move    %sp, %usp
     sub     #USER_STACK_LENGTH, %sp         // configure a USER_STACK_LENGTH bytes user stack at bottom, and system stack on top of it
 
+    move.l  #0xA11100,%a0       /* Z80_HALT_PORT */
+    move.w  #0x0100,%d0
+    move.w  %d0,(%a0)           /* HALT Z80 */
+    move.w  %d0,0x0100(%a0)     /* END RESET Z80 */
+
     jmp    _start_entry