Open MESS issues

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TI-99/8 Extended Basic II with selected floppy controller locks up on start

Symptom: When selecting Extended Basic II, the floppy is accessed, and then the emulator is trapped in an endless loop. This does not occur if no floppy controller is active.
Reason: The TI-99 DSR in Extended Basic II assumes that PABs can also reside in CPU RAM. However, this is not supported by the DSRs in the expansion cards. Accordingly, the PAB is not found, and Extended Basic II does not properly handle this case and crashes.
Workaround: Any other cartridge (like Editor/Assembler) works, so you have no floppy support in Extended Basic II, and this cannot be repaired, since the error is in Extended Basic II. Hexbus devices may be supported, but this is not available in MESS yet.


Geneve fails to boot from disk

Symptom: The Geneve does not boot from disk when the disk is inserted too late. Once the "CANNOT READ FROM FLOPPY DISK" appeared (because there was no disk in the drive), it fails to read the disk on retry.
Workaround: Ensure that a boot disk is inserted when starting. Or try to pause the emulation (partial mode, press p), insert the disk, and continue.

Serial output does not work

I have not yet managed to write output to the emulated RS232 interface.

Slow performance

Symptom: The emulator has a bad performance. Sound comes chopped from the speakers. Earlier versions performed much better.
Workaround: Keep the window small. Larger windows or fullscreen display cause a high CPU load. Using the "opengl" setting in mess.ini may help. Use the F9 key to increase the skip rate (in Partial mode).

BwG controller reports bad diskette

Symptom: The BwG controller reports a bad diskette (Disk Error 16) on Quick Test in Disk Manager II or I/O error in TI BASIC. This occurs

  • on all drives except DSK1
  • with all valid formats
  • on the first test with that drive; the next attempt is successful
  • if DSK1 has not been tested before
  • at least since MESS 0.99

Possible reason: Drives higher than DSK1 are not properly initialized.
Workaround: Access DSK1 first.

Other controllers (TI FDC, HFDC) do not have this issue.

Update: TI FDC has the same problem, only HFDC works correctly.

Geneve's color palette

Symptom: After resetting with Ctrl-Shift-Shift from a program (Fractals), the text color is red or other colors have changed (i.e. background). Does not get fixed with another reset.
Reason: Unknown

Geneve joystick

Symptom: Joystick in native mode has been reported not to work. Needs verification.

Keyboard issues with natural keyboard

Symptom: Natural keyboard keyboard sluggish; key repetition interferes with TI key handling