06639: coco3, coco3h: crash of emulated system accessing multiple floppy drives

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
06639	Crash/Freeze	Critical (emulation)	Always	Aug 1, 2017, 04:59	Aug 4, 2017, 06:39

Tester	drencorxeen	View Status	Public	Platform	MAME (Official Binary)
Assigned To	Duke	Resolution	Fixed	OS	Windows 10 (64-bit)
Status [?]	Resolved			Driver	trs/coco3.cpp
Version	0.188	Fixed in Version	0.189	Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	06639: coco3, coco3h: crash of emulated system accessing multiple floppy drives
Description	mounting OS-9 L2 or NitrOS-9 L2 in drive 0 and mounting another disk in drive 1 and doing drive access on both drives crashes emulated system.
Steps To Reproduce	Mount OS-9 L2 or NitrOS-9 L2 boot disk in drive 0 Mount another disk image in drive 1 with OS-9 files on it. type DOS at disk basic prompt to boot into OS-9 L2 or NitrOS-9 L2 Once at OS-9 L2 command prompt I type: shell i=/w7&<ENTER> load dir<ENTER> >-Press CLEAR key (HOME)-< On new window type: chd /d1 ; chx /d1/cmds<ENTER> dir x e; dir x e; dir x e; dir x e; dir x e; dir x e; dir x e; dir x e; dir x e; dir x e <HOME> Now we are back on term window we type: dir x e; dir x e; dir x e; dir x e; dir x e; dir x e; dir x e; dir x e; dir x e; dir x e <HOME> Now that we are back on Windows W7 we press <ENTER> then we press <HOME> Now we should be back on the TERM window and we press <ENTER> If all goes correctly the dir command should be doing directories of both /d1/cmds and /dd/cmds which should freeze or cause interesting patterns on the emulated system.
Additional Information	Video I made showing the steps I took as well.
Github Commit

Flags
Regression Version
Affected Sets / Systems	coco3, coco3h

Attached Files

No.14044 drencorxeen Tester Aug 1, 2017, 16:11	After more testing I found this might have to do with the FDC emulation. I did some tests in Disk Basic and found that FDC is not switching to the correct Disk Image/Drive# correctly. Steps I was able to do this and reproduce the problem: start MAME and launch CoCo 3 or CoCo3h create new disk image in drive 0 create new disk image in drive 1 DSKINI0 DSKINI1 DIR 1 type in basic program: 10 PRINT "DIR 0" 20 DIR 0 30 PRINT "END DIR 0":PRINT "DIR 1" 40 DIR 1 50 PRINT "END DIR 1" 60 GOTO 10 DIR 0 SAVE "TEST1.BAS" DIR 0:DIR 1 Now you should see the contends of the directory on drive 0 showing up on drive 1 as well. If you do a DIR 0 wait a few seconds for drive motor to shut off and then do DIR 1 The expected empty directory shows up. Now if you do a DIR 1:DIR 0 You will get a blank directory for both drive 1 and drive 0. So for some reason the FDC subsystem seems to not be switching between the drives correctly. As a side note I have tested this in the Official MAME 0.188 32bit & 64bit binaries and it does the same thing.
No.14045 star2root Viewer Aug 1, 2017, 16:18	Also effects the CoCo 2b. I have not confirmed it yet but I strongly suspect all CoCo 1, 2, and 3 systems with a floppy controller are effected. If you want to try it out the simplest way to show this off is to do this: Startup CoCo 2 or CoCo3 emulation Create a new disk image and mount it in drive 0 Create a new disk image and mount it in drive 1 I used blank JVC disk images created by MAME. Then... DSKINI 0 DSKINI 1 Enter a quick basic program like this and save it to disk: 10 PRINT "DIR 0" 20 DIR 0 30 PRINT "DIR 1" 40 DIR 1 50 GOTO 10 SAVE"TEST1.BAS" Content of the program is not important, although this program will further illustrate the problem Then all you have to do to see the problem is to: DIR 0:DIR 1 It can also be produced by typing DIR 0 DIR 1 on separate lines, if it is typed in fast enough.
No.14050 drencorxeen Tester Aug 1, 2017, 21:35	More information I have done to test. I went back to version 0.162 testing the FDC problems. I found my FDC problems seem to have started with version 0.163 of MAME.
No.14066 drencorxeen Tester Aug 4, 2017, 06:39	Ok so the commit that was made for a fix for the coco_fdc.cpp did seem to correct this issue at this time. I have been running the emulated system for hours now without any crashes.