atari800 software package provides Atari 8-bit emulator for SDL, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install atari800
atari800 is installed in your system.
Make ensure the atari800 package were installed using the commands given below,
$ sudo dpkg-query -l | grep atari800 *
You will get with atari800 package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Other OSs and file systems |
| Package | atari800 |
| Version | 3.1.0-2+b1 |
| Description | Atari 8-bit emulator for SDL |
| Sub Section | Otherosfs |