When you start Frodo you are presented with a settings window. Most settings have reasonable defaults, so there should be very little you have to configure:
C64 joysticks are typically digital devices with eight directions and just one button. Frodo lets you use the D-pad and left stick of the controller for the direction, and the “A” (or Cross) face button as the joystick button. The “Button Mapping” function lets you assign additional controller buttons to keys on the C64 keyboard, depending on the game you want to play.
Note that most C64 games use a joystick in Port 2 by default, even if they are single-player. If you don't get a reaction from controller input, try the “Swap Joysticks” option to exchange the port assignments.
If you don't have (or want to use) a game controller, Frodo also offers a joystick simulation on the numeric keypad. The “5” and “0” keys act as the joystick button while the other number keys control the direction. Press the Num Lock key to switch between joystick Port 1 and 2.
You can also use the Enter key on the numeric keypad to change the display mode on the fly while the emulator is running.
Frodo supports software written for the Commodore 1541 disk drive, the “Datasette” tape drive, and also many game cartridges. The disk drive was the most popular option back in the day, so most software you will now find comes in the form of .D64 disk image files (no, they are not called “ROMs”!). Press the file selection button next to the “Drive 8” label to choose a .D64 file to mount in the simulated drive with drive number 8.
(For advanced users: If you deselect the “Enable Full 1541 Emulation”, Frodo will let you use up to four simulated disk drives and switch to a faster and more flexible “virtual” 1541 drive emulation which also lets you access entire directories of the host computer from the C64. This works well with simple, single-file games, but for most uses the “full” 1541 emulation is recommended.)
The C64 is a Personal Computer, not a games console, and it doesn't normally auto-run software from the disk drive. Instead it comes with a built-in text adventure game in the form of an interpreter for (a simple implementation of) the BASIC programming language.
(If you're feeling adventurous, take a look at the Commodore 64 User's Guide and work through the included BASIC programming exercises. Maybe you'll eventually become a famous software developer and author of a C64 emulator!)
Getting software to load and run from the simulated disk drive also usually involves typing in some BASIC commands. Luckily, Frodo has an “auto-start” feature which types in the necessary commands for you.
Click on the “Auto-Start From Drive 8” button to close the settings window and start the emulator with the .D64 image you have mounted in drive number 8. You will now see the beautiful, blue startup screen of the Commodore 64 with the iconic “READY.” prompt and a LOAD command executing.
Important key combinations inside the emulator window:
If the C64 displays a “LOADING” message after auto-starting, things are looking good. If you instead get an error message you most likely forgot to mount a .D64 file, or mounted the wrong disk of a multi-disk game. Also check any documentation that came with the software for the command that should be used to run it (this was often printed on the disk label). It may be something different like LOAD"BOOT",8,1.
When typing in commands, be aware that Frodo simulates the original layout of the Commodore 64 keyboard, so the " (quote) character is on Shift-2, and the * (star) is most likely to be on the “]” (right bracket) key, or the equivalent key in the same position on national keyboards. Don't worry, you'll get used to that.
If manually entering a LOAD command still doesn't give you results, then try:
LOAD"$",8
Wait for that to finish and get back to the “READY.” prompt, then type:
LIST
This will give you a listing of the directory contents of the .D64 file (if it scrolls off the screen too quickly you can hold down the Tab or Ctrl key to slow it down). Sometimes there are instructions for how to load the software embedded in the directory listing. Otherwise, note down the name of the first file with a “PRG” designation next to it and try entering:
LOAD"<filename>",8,1
where “<filename>” refers to the file name you noted down.
If you successfully got a “LOADING” message, there's basically two things that can happen next:
If the game did not start automatically and you're back at the “READY.” prompt after loading, enter this to start the game:
RUN
You should now be good to go. Some games (especially those which had their original copy protection removed by some friendly people caring about game preservation) may show weird characters or flickering color bars for a few seconds before things start. This is normal. Some games also present an intro or title screen that needs to be skipped by pressing the Space bar or a joystick button. If a game asks you to press “RUN/STOP”, hit the Escape key. The “Commodore” or “C=” key is mapped to the Alt keys.
To quit Frodo, either close the emulation window, press Alt-F4, or press F10 to bring up the settings window and click on “Quit”.