65816: add Absolute,Y addressing mode to STA

twvd · Oct 15, 2023 · 0a02a72 · 0a02a72
1 parent 7a277fb
commit 0a02a72
Show file tree

Hide file tree

Showing 2 changed files with 7 additions and 1 deletion.
diff --git a/src/snes/cpu_65816/cpu.rs b/src/snes/cpu_65816/cpu.rs
@@ -266,6 +266,12 @@ where
                 .wrapping_add(Address::from(self.regs.read(Register::X)))
                     & ADDRESS_MASK
             }
+            AddressingMode::AbsoluteY => {
+                (Address::from(self.regs.read(Register::DBR)) << 16
+                    | Address::from(instr.imm::<u16>()?))
+                .wrapping_add(Address::from(self.regs.read(Register::Y)))
+                    & ADDRESS_MASK
+            }
             AddressingMode::StackS => Address::from(
                 self.regs
                     .read(Register::S)

diff --git a/src/test/processortests_65816.rs b/src/test/processortests_65816.rs
@@ -290,7 +290,7 @@ cpu_test!(instr_95, 0x95);
 cpu_test!(instr_96, 0x96);
 cpu_test!(instr_97, 0x97);
 cpu_test!(instr_98, 0x98);
-//cpu_test!(instr_99, 0x99);
+cpu_test!(instr_99, 0x99);
 cpu_test!(instr_9a, 0x9a);
 cpu_test!(instr_9b, 0x9b);
 cpu_test!(instr_9c, 0x9c);