These past weeks were dedicated to the improvement of VDISK's graphical interface. The present release includes a handful of interesting functionalities like:

• Open DSK and DMK files by just double-clicking over them
• Choose whether to detect file formats automatically or manually
• Choose whether to show or hide system and invisible files
• Sort files by name, extension, size, date and attributes
• Export multiple selected files at once
• See disk properties including name, date, DOS version etc.
• Navigate through disk sectors

Check the VDISK page for screenshots and additional information. The next version will sport some writing capabilities as well as drag & drop support. Don't forget to report any bugs you may find in the meanwhile.

VDISK went through an extensive reorganization and debugging process during the past three weeks. Now 80% of all known TRS-80 Model I/III/4 operating systems are correctly addressed by the program. Important bugs have been fixed, making crashes and other strange behaviors very unlikely to happen.

Here is a summary of changes for version 0.4:

• Addition of support to TRSDOS 1.1, NEWDOS/80 1.0, LS-DOS 6.3.1 and MICRODOS 1.12 (experimental)
• Inclusion of four quietness levels to better control the program verbosity ("/Q" parameter)
• Reordering of the OS detection routines in automatic mode to improve their overall accuracy
• Renaming of the OS command-line names to facilitate their memorization
• Improvement of the NEWDOS/80 identification algorithm
• Inclusion of a check against empty files in the GET routine of the command-line interface
• Correction of a bug in the DUMP routine of the command-line interface which prevented it to show the last sector of disks whose sector numbering starts in 1 instead of 0
• Correction of a bug in the NEWDOS/80 module which caused the file seeking functions to return an error when reading the 32nd entry of the HIT, due to an unusual usage of that entry by the OS
• Correction of a bug in the DMK module that led it to report incorrect disk densities for some disks
• Correction of a bug in the DMK module that caused some incorrect sector readings (thanks to David Sutherland for pointing this out)
• Correction of a bug in the DMK module which resulted in reading errors when only one side of a double-sided disk is formatted

The focus for the next release will be the graphical user interface. In the meanwhile, please report any bugs you may find using the contact form available from the top menu.

This program can be freely downloaded from the downloads page.

On August 16th, Prof. Gustavo E.A.P.A. Batista shared with our virtual community the first CP-500 ROM dump, making the emulation of that computer even more similar to the real machine.

The CP-500 ROM has 16kB, against 14kB of the standard TRS-80 Model III. According to Matthew Reed's first analysis, "the CP-500 ROM differs from the Model III ROM in fewer than 90 bytes, many of which are changed messages. The extra 2K appears to be a machine language monitor".

It is possible to run the CP-500 ROM with Matthew's TRS32 but, for that to work, DOS500 is also required. After placing the ROM in the proper folder and booting the OS, remove the disk from the drive and reset the emulator. You should see the messages "Cass?", "Mem. usada?", "PROLOGICA 1981 BASIC" and "READY>".

Notice that the resident Monitor won't work due to a supposed addressing conflict, but it is possible to see its prompt by entering the command "SYSTEM". Matthew mentions that he has plans to add support for TRS-80 clones in the future, including the CP-500. We are looking forward to it!

The CP-500 ROM is available for download here.