From 894cb257ada6b6ab904c173233668284533eb478 Mon Sep 17 00:00:00 2001
From: Chris Anders <filmee24@gmail.com>
Date: Sun, 27 Oct 2024 11:04:49 +0100
Subject: [PATCH] feat: Add Stack BusActivations

---
 src/MimaSim/MimaSim/MIMA/Components/Stack.cs | 14 +++++++++++++-
 src/MimaSim/MimaSim/MIMA/ErrorCodes.cs       |  3 ++-
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/src/MimaSim/MimaSim/MIMA/Components/Stack.cs b/src/MimaSim/MimaSim/MIMA/Components/Stack.cs
index 6bd6d01..2a8b03e 100644
--- a/src/MimaSim/MimaSim/MIMA/Components/Stack.cs
+++ b/src/MimaSim/MimaSim/MIMA/Components/Stack.cs
@@ -1,4 +1,6 @@
-namespace MimaSim.MIMA.Components;
+using MimaSim.Core;
+
+namespace MimaSim.MIMA.Components;
 
 public class Stack(CPU cpu)
 {
@@ -9,10 +11,18 @@ public void Push()
         var sp = cpu.ControlUnit.SP.GetValue();
         var value = cpu.Accumulator.GetValue();
 
+        if (sp < 0)
+        {
+            cpu.ControlUnit.SetError(ErrorCodes.StackOverflow);
+            return;
+        }
+
         Data[sp] = value;
         sp--;
 
         cpu.ControlUnit.SP.SetValue(sp);
+
+        BusRegistry.Activate("cu->stack");
     }
 
     public void Pop()
@@ -24,5 +34,7 @@ public void Pop()
 
         sp++;
         cpu.ControlUnit.SP.SetValue(sp);
+
+        BusRegistry.Activate("cu->stack");
     }
 }
\ No newline at end of file
diff --git a/src/MimaSim/MimaSim/MIMA/ErrorCodes.cs b/src/MimaSim/MimaSim/MIMA/ErrorCodes.cs
index 301098f..0086426 100644
--- a/src/MimaSim/MimaSim/MIMA/ErrorCodes.cs
+++ b/src/MimaSim/MimaSim/MIMA/ErrorCodes.cs
@@ -3,5 +3,6 @@
 public enum ErrorCodes
 {
     Unknown,
-    SysCallNotFound = 0x01,
+    SysCallNotFound,
+    StackOverflow
 }
\ No newline at end of file