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ID Category [?] Severity [?] Reproducibility Date Submitted Last Update
05985 Crash/Freeze Critical (emulator) Always Jul 11, 2015, 10:45 Dec 31, 2017, 23:47
Tester MetalliC View Status Public Platform
Assigned To Resolution Open OS
Status [?] Confirmed Driver
Version 0.163 Fixed in Version Build
Summary 05985: Z80 CPU core can't handle many IX/IY (0xdd/0xfd) instruction prefixes in a row
Description code in provided example software do follwing -
fills big RAM area with 0xFD and jump there

as result I see in error log a lot of "Z80 ':maincpu' ill. opcode $fd $fd" messages and then emulator exits, silently, without printing any callstack messages.
I think stack overflow happens.
Steps To Reproduce - unpack provided floppy image to MAME folder
- run "mame pentagon -flop1 fuckemul.trd"
- select TR-DOS (cursor up, enter)
- RUN (r, enter)
shortly emulator silently closes for me, other user reported appcrash message
Additional Information
Regression Version
Affected Sets / Systems
Attached Files
zip file icon (1,710 bytes) Jul 11, 2015, 10:45 Uploaded by MetalliC
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Jul 11, 2015, 17:56
edited on: Jul 11, 2015, 17:59
Do we have any confirmed way to run this on real hardware and have it be something that we can actually see operate correctly - are there any visual clues built into the program that will let us know it works or doesn't other than exception crashing?

That said, I do get an exception, but no stack:
Exception at EIP=0000000002CC2966 (z80_device::illegal_1()+0x00a6): STACK OVERFLOW