summaryrefslogtreecommitdiffstatshomepage
diff options
context:
space:
mode:
author Peter Ferrie <peter.ferrie@gmail.com>2023-02-27 09:23:05 -0800
committer Peter Ferrie <peter.ferrie@gmail.com>2023-02-27 09:23:05 -0800
commit410a3dbeae2021a357dc2da96c17e189adb715cf (patch)
tree71c946c8235cf5bef3ec1c38c58c760fe5edcb36
parentdeceecfbfb3fc639162dd58026bb1d729c107fa6 (diff)
apple2gs.cpp: don't allow read of write-only switches, fixes MT08564 [Peter Ferrie]
-rw-r--r--src/mame/apple/apple2gs.cpp25
1 files changed, 4 insertions, 21 deletions
diff --git a/src/mame/apple/apple2gs.cpp b/src/mame/apple/apple2gs.cpp
index a714fd112b0..d8278ba9017 100644
--- a/src/mame/apple/apple2gs.cpp
+++ b/src/mame/apple/apple2gs.cpp
@@ -1501,29 +1501,12 @@ u8 apple2gs_state::c000_r(offs_t offset)
switch (offset)
{
- case 0x00: // keyboard latch
+ // keyboard latch
+ case 0x00: case 0x01: case 0x02: case 0x03: case 0x04: case 0x05: case 0x06:
+ case 0x07: case 0x08: case 0x09: case 0x0a: case 0x0b: case 0x0c: case 0x0d:
+ case 0x0e: case 0x0f:
return uKeyboard;
- case 0x02: // RAMRDOFF
- m_ramrd = false;
- auxbank_update();
- break;
-
- case 0x03: // RAMRDON
- m_ramrd = true;
- auxbank_update();
- break;
-
- case 0x04: // RAMWRTOFF
- m_ramwrt = false;
- auxbank_update();
- break;
-
- case 0x05: // RAMWRTON
- m_ramwrt = true;
- auxbank_update();
- break;
-
case 0x10: // read any key down, reset keyboard strobe
keyglu_816_write(GLU_C010, 0);
return uKeyboardC010 | (uKeyboard & 0x7f);