From ecb3f0745952819d7b0351821496be508180c07c Mon Sep 17 00:00:00 2001
From: Andrew Keeton <andrewrkeeton@gmail.com>
Date: Thu, 6 Nov 2014 19:30:05 -0500
Subject: [PATCH 1/3] Add branch_if_carry_clear_test().

---
 src/machine.rs | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/machine.rs b/src/machine.rs
index e95411d..6175778 100644
--- a/src/machine.rs
+++ b/src/machine.rs
@@ -860,6 +860,19 @@ fn jump_test() {
     assert_eq!(machine.registers.program_counter, addr);
 }
 
+#[test]
+fn branch_if_carry_clear_test() {
+    let mut machine = Machine::new();
+
+    machine.execute_instruction((instruction::SEC, instruction::UseImplied));
+    machine.branch_if_carry_clear(Address(0xABCD));
+    assert_eq!(machine.registers.program_counter, Address(0));
+
+    machine.execute_instruction((instruction::CLC, instruction::UseImplied));
+    machine.branch_if_carry_clear(Address(0xABCD));
+    assert_eq!(machine.registers.program_counter, Address(0xABCD));
+}
+
 #[test]
 fn branch_if_minus_test() {
     {

From be7539d6c92f7d9a2d1b62e8bc9f2bd9687656c9 Mon Sep 17 00:00:00 2001
From: Andrew Keeton <andrewrkeeton@gmail.com>
Date: Thu, 6 Nov 2014 19:32:15 -0500
Subject: [PATCH 2/3] Add branch_if_carry_clear().

---
 src/machine.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/machine.rs b/src/machine.rs
index 6175778..73f5596 100644
--- a/src/machine.rs
+++ b/src/machine.rs
@@ -541,6 +541,12 @@ impl Machine {
         self.registers.program_counter = addr;
     }
 
+    fn branch_if_carry_clear(&mut self, addr: Address) {
+        if !self.registers.status.contains(PS_CARRY) {
+            self.registers.program_counter = addr;
+        }
+    }
+
     fn branch_if_minus(&mut self, addr: Address) {
         if self.registers.status.contains(PS_NEGATIVE) {
             self.registers.program_counter = addr;

From 7a4515b375e7dfdbd96684e5d65499d62d954879 Mon Sep 17 00:00:00 2001
From: Andrew Keeton <andrewrkeeton@gmail.com>
Date: Thu, 6 Nov 2014 19:35:07 -0500
Subject: [PATCH 3/3] Add BCC to execute_instruction.

---
 src/machine.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/machine.rs b/src/machine.rs
index 73f5596..357b01b 100644
--- a/src/machine.rs
+++ b/src/machine.rs
@@ -110,6 +110,13 @@ impl Machine {
                     &mut self.registers.status);
             }
 
+            (instruction::BCC, instruction::UseRelative(rel)) => {
+                let addr = self.registers.program_counter
+                         + AddressDiff(rel as i32);
+                self.branch_if_carry_clear(addr);
+            }
+
+
             (instruction::BIT, instruction::UseAddress(addr)) => {
                 let a: u8 = self.registers.accumulator as u8;
                 let m: u8 = self.memory.get_byte(addr);