Hi guys,
I just spent a few hours setting up DOSBox on PocketGo. I decided to write this post to save someone their precious time. This post should actually appear in "DOSBox Guides" but I can't post it there.
So, here goes.
I have PocketGo 2 v2 Keep that in mind.

1. List of emulators is available here https://github.com/retrogamehandheld/OpenDing … ttes-cheats-etc
As you can see DOSBox can be downloaded from https://github.com/retrogamehandheld/Op ... -12%20.opk

2. When you put this file into your apps folder and start DOSBox once you should be able to find the conf file in /usr/local/home/.dosbox
My conf file is named dosbox-SVN.conf

3. You can now download a DOS game. I wanted to play Crazy Digger. So I found it here: https://www.abandonwaredos.com/abandonware-ga … Digger&gid=1868

4. The game was too fast. So I edited dosbox-SVN.conf:
cycles=fixed 500

5. The PocketGo's joystick controls left, right, up, down. It works out of the box. But how do I get "A" button to act as 'fire'? This is the most interesting part.
If you push the left bumper you get to see the virtual keyboard. Press F1 virtually and you get 'fire' (In Digger, that's how the game works). Now we need to map it to the 'A' button of PocketGo.

For that I downloaded DOSBox for Windows and learned how to use Mapper.
https://www.dosbox.com/wiki/Mapper

My recommendation for PocketGo:
- start KeyMapper and save mapper-*.map file for the first time. It should appear in C:\Users\<username>\AppData\Local\DOSBox
- the format of this file:
left side - what you want to send to DOS,
right side - what you actually press 'here'

- so how do you know what you actually press 'here' if you are dealing with a PocketGo device?
There is an app called PocketGo2 v2 test in applications tab. Start it to find out that:
A is 306, B - 308, Y - 304, X -32.
You can also find codes for bumper buttons and everything else. So now you can fully equip them when interacting with the DOSBox emulator.

6. Take the mapper-*.map file generated by Mapper on your PC and append codes that you need.
In my case it is:
key_f1 "key 282" "key 306"

So now 2 external keys are mapped to F1 in DOS.
What are those external keys? - F1 and A button.
Since I don't have F1 on PocketGo I cannot press it, but I can use 'A' button.

7. Put that mapper file next to the conf file. IMPORTANT: those two files should have same suffix. -SVN in my case. So:
dosbox-SVN.conf
mapper-SVN.map
If you use a different name DOSBox will silently ignore your file.

That's it. Keymapping is simple but a few things are not evident.
I hope this little guide helps someone in setting up their DOSBox on PocketGo.