EmuNations

--4.40 TEST3--

• Fixed crash in devices tree when adding new devices with certain nodes selected.

• Fixed console key input bindings in input maps being disabled in full screen mode.

• The Add Device dialog now has device names sorted.

• Fixed D3D11 bloom rendering with incorrect gamma in full-screen mode.

• Moved screen mask rendering to post color correction to reduce aliasing artifacts.

--4.40 TEST2--

• Adds full 850 Interface Module emulation.

• 850 standard emulation now matches the transfer speed of the 850, and fixed an issue with inconsistent DTR/RTS state.

• Updated internal 850 R: handler to v0.3 so it matches the Break key behavior of the newer 850 firmware instead of the older 850 firmware.

• On-screen error decoder (Ctrl+Alt+click) now interprets 850-specific CIO error codes.

• SIODATA logging channel now detects and interprets command frames.

• Added vertical slot mask type to mask rendering.

• Fixed a crash in custom device error reporting code.

More detailed explanation of the 850 stuff:

Like the other full emulators, 850 full emulation means that it is running the actual controller firmware instead of a high-level emulation of the 850. This also comes with the usual caveats: it requires the actual firmware, and some quality-of-life features aren't available with it, such as unthrottled operation. However, it also means you can test real corner cases like running code on the emulated 850 (and yes, warerat's firmware dumper does work). One caveat is that in some cases you may need to specify the baud rates for each port in the settings. This is because with full emulation, the emulator no longer has a direct way to tell what baud rate the 850 is using or expecting on each port, and this causes problems with output paths that are baudless like the file writer. Currently, the Auto detection will attempt to match POKEY's baud rate. This should work for the majority of cases that use concurrent I/O, but it may fail with the uncommonly used block write feature unless a specific baud rate is specified.

The full emulation also reveals a couple of things about the firmware. There are two firmware revisions in the wild, with CRC32s 9201359A and 2CF990B9. The [9201359A] firmware is the older revision and [2CF990B9] is the newer and more common revision. The 850 firmware sources from the Atari History Museum match the newer revision. The main differences between the two are documented in the different versions of the 850 Interface Manual, with the 1980 Owner's Manual documenting the older revision and the 1982 Technical Manual documenting the newer revision, with a note on getting older 850s upgraded at a service center. The main difference between the two is the handling of the Break key when concurrent I/O is active. In the older revision, pressing Break causes the R: handler to autonomously exit concurrent I/O mode, whereas in the newer revision, the Break key is disabled and ignored. However, there are also two undocumented changes: the newer revision also recognizes P2: for printer access, and raises the printer I/O timeout from 5 seconds to 30 seconds. The relocator and handler downloads are slightly longer on the older revision as well, meaning that some software won't work with it -- notably BobTerm can't auto-download the R: handler.

Accordingly, a couple of adjustments have been made to the 850 standard emulation to improve accuracy. The internal R: firmware that's built-in and included on the Additions disk has been updated to v0.3 with the Break key behavior now matching the newer firmware, and the transfer rate of the firmware download has been slowed down to match the 850, which like the 1050 is a little bit on the slow side. A fix has also been made to control signal handling as DTR and RTS weren't consistently being set on the attached device. The main potential impact of this is that the modem will not auto-answer on default settings unless DTR is asserted or the DTR handling mode is changed with the AT&D command. BobTerm at least makes sure that DTR is asserted at startup, but other software might not.

Finally, in not 850 related news, slot mask support has been added, which is a mask type with fine vertical slots instead of unbroken vertical stripes as in an aperture grille. It is the mask type used by at least some versions of the Commodore 1702 monitor.

--4.40 TEST1--

Adds support for display screen mask emulation, currently supporting aperture grille (Trinitron) and dot triad patterns. This is set up in View > Adjust Screen Effects. It works best with a high resolution display (e.g. 2560x1440 or higher) with high brightness or HDR enabled, as this requires even higher peak brightness than scanlines. The renderer will try to compensate if bloom is enabled, but you'll see moiré patterns on bright colors if you push it too hard.