From 6ab729f377678c5682c4adb18a933aaf2385ea16 Mon Sep 17 00:00:00 2001
From: Matthew Laux <matthew.laux@gmail.com>
Date: Tue, 26 Jul 2022 00:10:01 -0500
Subject: [PATCH] it goes off the rails at the gameplay screen on tetris

---
 src/cpu.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/cpu.c b/src/cpu.c
index 112aeb5..1666d77 100644
--- a/src/cpu.c
+++ b/src/cpu.c
@@ -705,6 +705,9 @@ void cpu_step(struct cpu *cpu)
             write8(cpu, read_hl(cpu), cpu->a);
             write_hl(cpu, read_hl(cpu) - 1);
             break;
+        case 0x39: // ADD HL, SP
+            add16(cpu, cpu->sp);
+            break;
         case 0xc0: // RET NZ
             if (!flag_isset(cpu, FLAG_ZERO)) {
                 cpu->pc = pop(cpu);