From c225b01d7124d5eb3ef8d19bbc06b31e01b401e3 Mon Sep 17 00:00:00 2001
From: folkert van heusden <mail@vanheusden.com>
Date: Sat, 19 Mar 2022 18:37:25 +0100
Subject: [PATCH] SOB fix

---
 cpu.cpp | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/cpu.cpp b/cpu.cpp
index 0d690dc..6d8ed58 100644
--- a/cpu.cpp
+++ b/cpu.cpp
@@ -529,12 +529,18 @@ bool cpu::additional_double_operand_instructions(const uint16_t instr)
 			}
 
 		case 7: { // SOB
-			uint16_t oldPC = getPC(); // FIXME gaat dit wel goed voor R7?
-			addRegister(reg, false, -1);
+			uint16_t oldPC = getPC();
+
+			if (reg == 7)
+				addRegister(reg, false, -2);
+			else
+				addRegister(reg, false, -1);
+
 			if (getRegister(reg, false)) {
 				uint16_t newPC = oldPC - dst * 2;
 				setPC(newPC);
 			}
+
 			return true;
 		}
 	}