From 339086d5973b4cc4ee721eb35ff2a195502f562c Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Tue, 17 Jan 2023 22:29:17 -0500
Subject: [PATCH] The Yamaha chips have more ports.

---
 Machines/MSX/MSX.cpp | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Machines/MSX/MSX.cpp b/Machines/MSX/MSX.cpp
index 52af973ef..20a974805 100644
--- a/Machines/MSX/MSX.cpp
+++ b/Machines/MSX/MSX.cpp
@@ -568,6 +568,11 @@ class ConcreteMachine:
 
 					case CPU::Z80::PartialMachineCycle::Input:
 						switch(address & 0xff) {
+							case 0x9a:	case 0x9b:
+								if constexpr (vdp_model() == TI::TMS::TMS9918A) {
+									break;
+								}
+								[[fallthrough]];
 							case 0x98:	case 0x99:
 								*cycle.value = vdp_->read(address);
 								z80_.set_interrupt_line(vdp_->get_interrupt_line());
@@ -600,6 +605,11 @@ class ConcreteMachine:
 					case CPU::Z80::PartialMachineCycle::Output: {
 						const int port = address & 0xff;
 						switch(port) {
+							case 0x9a:	case 0x9b:
+								if constexpr (vdp_model() == TI::TMS::TMS9918A) {
+									break;
+								}
+								[[fallthrough]];
 							case 0x98:	case 0x99:
 								vdp_->write(address, *cycle.value);
 								z80_.set_interrupt_line(vdp_->get_interrupt_line());