Viewing Issue Advanced Details
ID Category [?] Severity [?] Reproducibility Date Submitted Last Update
06879 Debugger Minor Always Feb 16, 2018, 19:22 Jun 17, 2020, 22:04
Tester drencorxeen View Status Public Platform MAME (Official Binary)
Assigned To Resolution Fixed OS Windows 10 (64-bit)
Status [?] Resolved Driver
Version 0.194 Fixed in Version Build 64-bit
Fixed in Git Commit Github Pull Request #
Summary MESS-specific 06879: coco2, coco2b, coco3: Debugger causing system emulation to not work correctly
Description When starting MAME/MESS with the -debug option on the command line the emulation will not boot from NitrOS-9 L1 correctly. The system when it is trying to load the CPU shows it is jumping to RAM locations that it shouldn't be doing.

When you don't use the -debug option the emulation works as expected without any problems.

So far I have tried this with the coco3.cpp and subsets of coco3, coco3h, and coco3p with same effect. So this behavor is also in other systems besides coco12.cpp
Steps To Reproduce From PowerShell or command prompt I type:
.\mame64.exe coco2 -flop1 NOS9_6809_L1_coco2_80d.dsk -debug
From within the emulated system I type:
Additional Information I also tried building current bleeding edge sources from github and the issue is still there as well.

So far I have only tested in coco12.cpp and coco3.cpp systems.
Github Commit
Regression Version
Affected Sets / Systems coco2, coco2b, coco3
Attached Files
zip file icon (179,306 bytes) Feb 16, 2018, 19:22 Uploaded by drencorxeen
NitrOS-9 L1 boot disk 3.5" 720K image
There are no relationship linked to this issue.
User avatar
Feb 16, 2018, 21:45
edited on: Feb 16, 2018, 22:02
Confirmed with -debug and image provided above on coco2 machine.
User avatar
Mar 5, 2018, 02:20
I have tested this on Ubuntu 16.04LTS 64bit and also doesn't work correctly there.
User avatar
Jun 17, 2020, 22:04
Not sure when this was fixed but have successfully booted NitrOS-9 L1 in coco2 and coco3 with -debug.