From 876ee194bcb1359753e460730a5b4183ae8b3b2d Mon Sep 17 00:00:00 2001
From: an_achronism <87213873+an-achronism@users.noreply.github.com>
Date: Wed, 1 Mar 2023 02:19:11 +0000
Subject: [PATCH] Unicomp New Model M broken Pause/Break key fix

The PS/2 controller code for Unicomp's current generation PS/2 keyboard
sends the wrong scancodes when Ctrl + Pause (which should be Break) is
pressed.

Instead of it sending the Break sequence...

    E0 7E E0 F0 7E

... representing a press of Scroll Lock, which is Break because Ctrl is
being pressed, it instead sends...

    E0 77

... representing a press of Num Lock, which is just the old way of
getting Pause.

Since the E0 77 coming from the controller is not a normal sequence,
this workaround does not interfere with Ctrl + Num Lock, which still
Pauses as it should.
---
 converter/ibmpc_usb/ibmpc_usb.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/converter/ibmpc_usb/ibmpc_usb.cpp b/converter/ibmpc_usb/ibmpc_usb.cpp
index 28895444..247d556c 100644
--- a/converter/ibmpc_usb/ibmpc_usb.cpp
+++ b/converter/ibmpc_usb/ibmpc_usb.cpp
@@ -914,6 +914,7 @@ uint8_t IBMPCConverter::cs2_e0code(uint8_t code) {
         case 0x72: return 0x3F; // cursor down
         case 0x74: return 0x47; // cursor right
         case 0x75: return 0x4F; // cursor up
+        case 0x77: return 0x00; // Unicomp New Model M Pause/Break key fix
         case 0x7A: return 0x56; // page down
         case 0x7D: return 0x5E; // page up
         case 0x7C: return 0x7F; // Print Screen