Altirra 2.6 Test 3 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 2.6 Test 3 Changelog:
Fixed the mixup in the hard disk dialogs, added missing XEGS game ROM category, made firmware loader prefer external firmware images over internal ones, added some missing .arc filters in file dialogs, changed the filter default from bilinear to sharp bilinear (+1), and removed the Ctrl+F1 filter shortcut by default (you will need to reset keyboard shortcuts to see this if you have already run Altirra before).
You need a 3D card capable of at least pixel shader 2.0 in order for the sharp bilinear setting to work. For the All-in-Wonder line, you will need at least a 9600 for this to work -- the original 7xxx and 8xxx series is too old. And if you have the original Rage based AIW... you're probably better off with software rendering. The Direct3D 9 or 11 display modes must also be active. If you have selected OpenGL or for some reason don't have 3D acceleration then you also won't get sharp bilinear.
The firmware image scan can only pick up images that are known. Currently it has entries for the original 5200, 800, XL/XE, XEGS, and 1200XL kernel ROMs, as well as the three main Atari BASIC revisions. It can't really pick up the other types of images because there's no solid way to detect that a ROM image is for, say, IDEPlus. I'm thinking of changing the Add dialog so that it asks what type of image is being chosen instead of having it determined by what category is selected, which is obscure.
Currently all firmware types other than OS kernel and BASIC can only have one firmware bound, as there is no place to choose it. Thought is that adding a way to mark an entry as (default) in the firmware dialog will allow for switching the more seldom used types of ROMs without cluttering up the main menus.

Download: Altirra 2.6 Test 3
Source: Here