From aa9a4c6bce98f27f49e7d631a6a93a432c54c5ec Mon Sep 17 00:00:00 2001
From: Thomas <thomas@thomasw.dev>
Date: Sat, 25 Nov 2023 23:04:01 +0100
Subject: [PATCH] SPC700: implement RET/RET1

---
 src/snes/cpu_spc700/cpu.rs        | 22 ++++++++++++++++++++++
 src/test/processortests_spc700.rs |  4 ++--
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/src/snes/cpu_spc700/cpu.rs b/src/snes/cpu_spc700/cpu.rs
index eb96644..810b1d8 100644
--- a/src/snes/cpu_spc700/cpu.rs
+++ b/src/snes/cpu_spc700/cpu.rs
@@ -283,6 +283,28 @@ where
             InstructionType::DAA => self.op_daa(),
             InstructionType::DAS => self.op_das(),
             InstructionType::JMP => self.op_jmp(instr),
+            InstructionType::RET => {
+                // Discarded read + internal cycle
+                self.read_tick(self.regs.read(Register::PC));
+                self.tick_bus(1)?;
+
+                let pc = self.pop16();
+                self.regs.write(Register::PC, pc);
+
+                Ok(())
+            }
+            InstructionType::RET1 => {
+                // Discarded read + internal cycle
+                self.read_tick(self.regs.read(Register::PC));
+                self.tick_bus(1)?;
+
+                let flags = self.pop8();
+                self.regs.write(Register::PSW, flags.into());
+                let pc = self.pop16();
+                self.regs.write(Register::PC, pc);
+
+                Ok(())
+            }
             _ => todo!(),
         }
     }
diff --git a/src/test/processortests_spc700.rs b/src/test/processortests_spc700.rs
index d7b6ad0..05e7d0c 100644
--- a/src/test/processortests_spc700.rs
+++ b/src/test/processortests_spc700.rs
@@ -303,7 +303,7 @@ cpu_test!(instr_6a, 0x6a);
 cpu_test!(instr_6d, 0x6d);
 // Read indirection during fetch
 cpu_test_no_trace!(instr_6e, 0x6e);
-//cpu_test!(instr_6f, 0x6f);
+cpu_test!(instr_6f, 0x6f);
 cpu_test!(instr_70, 0x70);
 cpu_test!(instr_71, 0x71);
 cpu_test!(instr_72, 0x72);
@@ -320,7 +320,7 @@ cpu_test!(instr_7a, 0x7a);
 //cpu_test!(instr_7c, 0x7c);
 cpu_test!(instr_7d, 0x7d);
 cpu_test!(instr_7e, 0x7e);
-//cpu_test!(instr_7f, 0x7f);
+cpu_test!(instr_7f, 0x7f);
 cpu_test!(instr_80, 0x80);
 cpu_test!(instr_81, 0x81);
 cpu_test!(instr_82, 0x82);