I have previously used Altirra 2.60 successfully. However, after switching to Windows 10, several months on the sick list, and upgrading to v.2.70, I find that Altirra no longer runs the cartridge files it did before for 5200 mode. Obviously, I am forgetting something. I have set Altirra to 5200 mode using the 5200 OS I used previously. I attach a cartridge and all I get is a black screen with the menu bar at the top.
What am I forgetting to get the emulator working . Any help would be appreciated. I love this program as it allows me to relive the 1980's when I was heavily invested in the Atari line.
Also, I am trying to find the ROM's for the ICD MIO. I am trying to virtually rebuild my Atari system from then. Thanks.