Task: Try an Atari 815 Disk Drive using the Altirra 8-Bit Emulator
Needed: Altirra Emulator
Time: 10-15 mins
Introduction
The Atari 815 dual disk drive was developed for release in 1980 but never made it to market. The 815 featured two single-sided and double-density drives housed in one unit. It has some unusual hardware design features and couldn’t read single (e.g. 810) or enhanced (e.g. 1050) density disks. Less than 100 were ever made and these were considered prototypes. As a result, this is an extremely rare piece of Atari 8-bit hardware. One recently sold on eBay for $10,000.
If you are curious, you can try a virtual 815 drive in the latest version of the Altirra emulator (v4.00).

Instructions
First, you will need to download version 4.00 or later or Altirra.
Second, you will need to download and install the 815 disk drive ROM. Navigate to the System menu and choose Configure System. On the left select Devices under Peripherals and click the Add button. Select 815 under Disk Drives. This will add the 815 drive to your virtual 8-bit computer. You should see warning that the firmware is not installed. Click on the Firmware manager button on the bottom right of the screen and choose the downloaded 815 ROM.
Third, you will need an ATR file compatible with the 815 disk drive. I downloaded the Atari DOS 2.0D (D = double-density) from the Atari Wiki. Go to the Altirra File menu and choose Attach Disk. Attach this DOS ATR file in drive 1.
Finally, do a cold boot into Altirra BASIC and type DIR and hit return. Type DOS and hit return to boot into DOS 2.0D. You just booted from a virtual 815 disk drive!
Here is a zip file with the ROM and ATR file.
Comments
I was fortunate to see the 815 drive Curt Vendel brought to VCF East a few years ago. Really too bad this never made it to market! Would be fun to have one.