Welcome !

ultraDev is a fpga based development cartridge for Atari computers.
A project i'm currently working on. It was for me more or less a learning project for FPGAs.
Check the pictures section to see it in action.

How does it works?
After a reset the Atari stays in an upload screen and waits for an upload from the host computer.
You can upload and start a prg-file from the host computer command line via USB. A prg file with 780kb needs around 0,94 seconds to start. So transferate is around 830kb/s.
The execution time of the prg-file is right before the auto-folder executes files from the folder. So the system is so far initialized.

With a small cable from inside the Atari the cartridge is able to reset the Atari. Which means you just run the command line tool again and the cartridge resets the Atari, uploads and starts the prg. No need to touch the Atari during development.

Btw. the cartridge 68k code itself can be uploaded via USB.

Why are you doing this?
a) Because i wanted to get more into FPGA things.
b) Yeah i know everyone is using a emulator nowadays but i like to code on real hardware. The main argument to use an emulator is (or was) the transfer to the real hardware. It's just to complicated to get the real hardware into the development process and work efficient. Sure you can code directly on the real hardware but tbh just a real pain in the ass and not state of the art anymore.
So ultraDev is designed to code and not only to do smaller tests. Why not use the Atari as a start-slave ?

How about debugging?
UPDATE:The cartridge has internal memory which holds the bugaboo debugger so it's resident and do not need to be uploaded every time.
The cartridge had memory to hold the Bugaboo resident but the speed gain is that small that i skipped it.
If you want to debug you can tell the command line tool to start bugaboo before and directly load the prg-file. Of course you will need a special version of bugaboo for this but it's included.
With the command line tool it is possible execute bugaboo commands after bugaboo loaded the prg-file. Very useful to set breakpoints or just execute automatically after loading.

You can use another debugger if you want but symbol loading works only with bugaboo.
Debug screen
You can connect a VGA monitor to the cartridge to output debug values on a separate screen. (Currently not finished)

Supported plattfroms
Currently only Windows is supported but the command line tool is standard c and should be easily compiled on other systems. The cartridge uses a FTDI chip for USB communication. The libraries are available for Windows, Mac OSX, Android and Linux.

The project is open source and feel free to build your own ;)

If someone really wants to build one i can deliver a home made pcb for it. The pcb will be a double sided pcb with soldering mask.
The cartridge uses a Xilinx Spartan 3 fpga development board (costs around 30€ which is available on ebay) + the cartridge pcb and some smaller parts.