With "Sprite display", you can switch the display of sprites on and off. Turning them off speeds up the emulation a little when there are a lot of sprites on the screen.
"Sprite collisions" determines whether collisions between sprites and between sprites and graphics should be detected. Turning off collisions will make you invincible in some games (sadly, your enemies are likely to become invincible, too :-/.
"Joystick on Port 1/2" specifies on which ports you have real joysticks connected (as opposed to the joystick emulation on the numerical keypad). Joysticks are only supported under BeOS, Linux and AmigaOS (only one joystick). The port numbers relate to the host machine ports. On the BeBox, port 1 is the upper one and port 2 the lower one. You should only turn on the ports to which you have actually joysticks connected, or the keyboard will behave erratically. Frodo has an automatic joystick calibration. If you plug in a new joystick or change the joystick settings, you should first move the joystick once in each direction.
With "Swap joysticks" you can swap the assignment of the joystick ports of the host machine to the C64 ports without having to plug out and in your joysticks. E.g. if a C64 game is using a joystick on C64 port 1 you can simply activate "Swap joysticks" and use a joystick in port 2 on your machine to play the game.
When the field "Limit speed" is active, the emulation is slowed down when its relative speed exceeds 100%. If you set the value in "Every (n)th frame" so that the speed is just over 100% and activate the speed limiter, the emulation always runs at the original C64 speed, with the highest possible precision.
With the setting "Fast Reset" you can disable the memory test that is normally performed by the C64 on a reset. Under emulation, the memory test is not necessary and the reset (F12) becomes much faster when it is disabled.
The setting "Clear CIA ICR on write" is necessary to make some programs (such as the games "Gyruss" and "Motos") run that would otherwise hang in an endless interrupt loop because they use an unusual technique to acknowledge CIA interrupts (sometimes even without the programmer knowing it). It should normally be turned off.
The "SID Filters" field enables the emulation of the SID filters. The sound emulation is slightly faster, but worse, when the filters are disabled.
"Doublescan lines" is only available under BeOS for the "Screen" display type. It removes the black lines between scanlines, but makes the emulation a bit slower.
"Cycles per line (CPU)" and "Cycles per Bad Line (CPU)" set the number of clock cycles available to the CPU per normal raster line and per Bad Line. If a program is showing flickering lines or graphical flaws you should try to slightly alter both values. For "Bruce Lee" you must enter "62" for the "Cycles per line (CPU)".
With "Cycles per line (CIA)" you can control the speed of the CIA timers. Entering a higher value increases the frequency of cursor blinking and key repeat. Some programs don't run correcly with the default value (e.g. "Ballblazer" which needs a value of 65).
"Cycles per line (1541)" sets the number of cycles available to the 1541 processor emulation per raster line. There is normally no need to change this value. This setting has no effect if 1541 processor emulation is turned off.
The settings for the four "cycles" coming closest to an original PAL C64 are (63, 23, 63, 64).
With "Draw every n-th frame" you can select if Frodo should skip frames when displaying the C64 graphics. The normal setting is "1", that is, every frame (every simulated raster beam sweep) is recalculated. If you change this to "2", for example, then only every second frame is calculated, immensely speeding up the display, though some raster effects may look a bit jerky. This setting can also be changed while the emulation is running with the '+' and '-' keys on the numerical keypad.
"Display type" is only available under BeOS. You can choose between running the emulation in a window or in full-screen mode (using the Game Kit).
The "SID emulation type" controls the sound emulation and has two settings: "None" and "Digital". "None" means no sound (faster), "Digital" turns on the digital sound emulation (only available under BeOS, Linux and HP-UX). Future versions of Frodo may support more emulation types such as the use of a real SID chip on an expansion card or across a network.
"REU size" sets the size of the REU (RAM Expansion Unit) emulated by Frodo or turns the REU emulation off ("None"). Only few programs actually use the REU (operating systems like ACE and GEOS, and some utilities).
In the box "Drives", there are four rows, each corresponding to one of four emulated 1541 drives with the drive numbers 8, 9, 10 and 11. For every drive, there is a popup control, a path entry field and a button:
With the popup control, you select the emulation mode of the respective disk drive (for more detailed information, see here). There are three choices: "Dir", "D64" and "T64". "Dir" emulates the drive in a directory of the BeOS/Unix file system. "D64" accesses a .d64 or x64 disk image file. "T64" is the setting for accessing a .t64 or C64 LYNX archive file.
The path entry field holds either the path name of the directory for the "Dir" mode, the path name of the .d64/x64 image file for the "D64" mode, or the path name of the .t64/LYNX archive file for the "T64" mode. Under BeOS, you may also drop Tracker icons to the entry field.
The button labeled "B" opens a file panel/requester for a more comfortable selection of directories and .d64/x64/.t64/LYNX files.
With "Map '/' <-> '\' in file names" you control whether the '/' in C64 filenames will be translated to '\' and vice versa for "Dir" mode drives. The '/' character is used to access subdirectories under BeOS/Unix, but as the C64 doesn't have subdirectories, it's a valid part of a C64 file name. This is a problem if a program wants to create a file with '/' in it as BeOS/Unix would interpret the part before the '/' as a directory name and, finding no such directory, would return an error and the operation would fail. Now simply activate this gadget and all '/'s will transparently be translated into '\', so in directory listings the '/' will still appear. If you turn off this option, you can of course use the '/' to access files in subdirectories from the C64.
If "Enable 1541 processor emulation" is turned on, the four emulated 1541s are disabled and replaced by a single 1541 emulation (drive 8) that only operates on .d64/x64 files, but emulates the 1541 processor and is compatible with about 50% of all fast loaders. However, it slows down the emulation considerably. If you have a .d64 with a program that doesn't load with the normal emulation (see above), you may have better luck with the 1541 processor emulation instead. The path name of the disk image file to be used must be entered into the path entry field of drive 8.
With the menu items "Open...", "Save", "Save As..." and "Revert" you can load and save the settings from and to arbitrary files.