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EmuCR:OpenMSX OpenMSX Git (2017/03/19) is complie. OpenMSX is an open source MSX emulator which is free according to the Debian Free Software Guidelines, available under the GNU General Public License.For copyright reasons the emulator cannot be distributed with original BIOS ROM images. OpenMSX includes C-BIOS a minimal implementation of the MSX BIOS, allowing to play quite some games without the need to have an original MSX BIOS ROM image. You can also use your own BIOS ROM image if you please.

OpenMSX Git Changelog:
* Support partial (cancelled) WD2793 write sector/track commands
Apparently these are used in DSK-PRO to write sectors with CRC errors. See this
thread for more details:
https://www.msx.org/forum/msx-talk/software/pdi-to-dmk-using-dsk-pro-104-with-openmsx
Supporting partial write commands was actually relatively easy. We already
emulated (most) writes with the correct timing. Though before this patch when a
write command was cancelled half-way, none of the writes were actually written
to disk. The reason for this is the following:
The WD2793 emulation always operates at the raw track level. Though usually
openMSX is used with .dsk disk images, those can only represent sector
information instead of the full track information. So at some point we need to
convert one format to the other. This conversion is not terribly expensive, but
also not cheap. So we don't do this after every written byte, but only once
after the full sector/track is written. Though before this patch when the write
command was cancelled we didn't do this conversion at all.
* Implemented 'deleted data mark' for WD2793 read/write sector
Initial attempt, might not be 100% accurate yet.
I verified that:
- Reading/writing 'normal' sectors still works.
- Formatting a disk still works.
- Writing a sector now completely rewrites the sector data including sync and
markers bytes at exactly 22 bytes after the sector header (as documented in
the WD2793 datasheet). Before the existing sector data block was reused,
even if that was positioned at a (slightly) different offset.
- I didn't explicitly test writing 'deleted sectors', but the code is quasi-
identical as writing normal sectors.
- I did hack a DMK image to have a deleted sector (with matching CRC) and
reading that sector on a NMS8250 still worked fine. I don't know whether a
real NMS8250 behaves the same. But it seems plausible if the disk ROM
software doesn't explicitly check the 'record type' status bit.

Download: OpenMSX Git (2017/03/19) x86
Download: OpenMSX Git (2017/03/19) x64
Source: Here

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