Altirra 2.4 Test 9

Altirra 2.4 Test 9 is released. Altirra is an Atari 8 bit Emulator on the Windows/DOS platform. Altirra emulates several models of the 8-bit Atari computers. This includes the the 800, 800XL, and 130XE versions. It has a lot of options, and compatibility is decent especially given the emulator's early stages. It also supports some copy protected games properly in emulation.

Altirra 2.4 Test 9 Changelog:

Took a crack at XEP-80 emulation: Enable in system menu, toggle from View menu. You must load an XEP-80 E: handler from disk to actually use it. Current versions of SpartaDOS X come with an XEP80.SYS handler on CAR: that can be used. Currently the emulation is hardwired to use joystick port 2. The XEP-80 is one weird beast, starting with it hooking up to the joystick port and then to the way the NS405 chip works. I don't actually have an XEP-80, so I had to cobble together everything from available sources. Emulation notes: No ROM images are needed, but I drew the character set manually so a couple of chars may be off, particularly in 50Hz mode when they are 13 scanlines tall instead of 10. Alt+Shift+X is the default shortcut to toggle the screen. I've also put in rudimentary support for automatic switching to/from the 80-column view -- goes to 40 on reset, back to 80 when data is sent to the XEP-80. Partial undocumented command support: $E1-E6, $ED, $EE, $F0, $F2, $F4, $F6, $F7, $F9, $FA. Overscan is currently not emulated in the UI layer, so you can see everything. The XEP-80 has massive overscan. The XEP-80 screen editor acts similarly but not quite the same as the standard Screen Editor. In particular, the Screen Editor works via a logical line start bitfield, whereas the XEP-80 actually stores EOLs in the framebuffer. I've attempted to emulate this behavior. The pixel aspect ratio is a guess based on the timing chain parameters. This is hard to determine because the XEP-80 appears to produce a video signal that is pretty far out of spec (16.3KHz horizontal??). Things I could use help with: Screenshots from the real hardware of the patterns produced by the internal character generator within the NS405. There's no information about the character set in the internal 7x11 ROM. Screenshots from the real hardware of the last part of the ATRIBUTE.BAS program from the XEP-80 disk where block graphics is activated. From what I've been able to tell, this can't work properly the way the program sets it up because the character set ROM generator is still active when block graphics is selected, which I wouldn't mind confirming. Any programs that have unusual usage patterns of the XEP-80, particularly: NS405 block graphics (hardware, not just the special ATASCII block graphics chars), custom underline/cursor settings, hardware scrolling in graphics mode, custom baud rates, mixed standard and international charsets on the same screen, or non-standard screen sizes or character widths/heights. An indication if anyone cares at all about the printer support. (The people in Atari's peripheral hardware division must have had some strange illness that made them add a parallel printer port to every device they made.)

Download: Altirra 2.4 Test 9
Source: Here