Unlike other C64 emulators, Power64 is capable of handling several emulated C64 at one time. The number of concurrent C64s is only limited by the available RAM. To create a new C64 select File/New (Cmd-N). Choose File/Close (Cmd-W) to close a C64 window no longer needed.
Even so the original C64 did not have a reset button built in, many people built one into their C64. Select File/Reset (Cmd-K) to reset the current C64 window. To force a hard-reset that circumvents the reset-protection of many games press the Option key while selecting File/Reset (or Option-Cmd-K).
To bring the C64 back to a well responsive state, when it is stuck in an endless loop (or something similar), the C64 featured the key combination Stop/Restore. This effect can be obtained in Power64 by selecting File/Stop/Restore (Cmd-R). Again pressing the Option key forces a hard Restore.
To quickly suspend all activity in a C64 window, select File/Freeze (Cmd-F). This will freeze the C64 until File/Freeze is activated again. To indicate the frozen state the window name will be surrounded by dots. This is a very useful feature, if you need to answer the phone or door in the middle of an exciting game. To conserve the current state of an C64 over longer periods of time see also: 4.4 RAM Images.
To create a hardcopy of the current C64 screen, select File/Print (Cmd-P). Depending on your printer you can choose to print either in color or in black/white. To print only a portion of the screen, click&drag the mouse to select the part of the screen that you are interested in. It is often advantageous to first Freeze the C64 (see above), so that the image does not change, before making a selection or hardcopy.
It is also possible to copy the contents of the C64 screen to insert it in a document of an other application. To do this click&drag the mouse to define the area of interest (or select Edit/Select All (Cmd-A) to select the entire screen) and then drag your selection to a suitable application, e.g. your favorite paint program or word processor and drop it there. Alternatively you can also choose Edit/Cut (Cmd-X) or (equivalently) Edit/Copy (Cmd-C) to copy the selected area. The clipboard will now contain a PICT image of the selected area that can be inserted in any paint program. If the C64s screen was in plain text mode the clipboard will also contain the selected screen area as TEXT, for insertion in a text editor or word processor.
It is also possible to paste text into a Power64 window. This makes it easy to develop a C64 program using your favorite Macintosh editor, and then 'type' it into the C64 via Drag&Drop or Cut&Paste. Try this with the Emulator detection program in Appendix F.
File/Quit (Cmd-Q) terminates Power64. (Surprise, Surprise).
A C64 can be connected to up to four 5.25" floppy disk drives (devices #8-11) and one modified (audio-)cassette tape recorder (device #1) called a Datasette. All these storage devices can be emulated by Power64.
Floppy disks are emulated most precisely using D64, X64, ZipCode, G41, D71 or D81 files (Appendix E.3 to E.7). To use a D64, X64, ZipCode, G41, D71 or D81 file, it is necessary to 'insert' it in the virtual disk drive using Devices/Disk Drive #x/Insert Floppy Disk. Once it is inserted it can be accessed like on a real C64 using BASIC or assembly language programs. If you are not familiar with C64 BASIC and are just interested in playing games see Section 2.4 to learn the necessary commands. To see what files are already available on the currently mounted disk choose Devices/Disk Drive #x/Display Directory. A window will be opened that shows the names and sizes (in Blocks of 254 Bytes) of all files on the disk. Double-click on a name, and the game will automatically be loaded. To remove a disk from a drive use Devices/Disk Drive #x/Eject Disk. Unlike on a real C64 Power64 will properly close all files before ejecting the disk. Note that Power64 will automatically eject the current disk when a new one is inserted.
Power64 features two modes of Floppy support. You can either have the Mac simulate the Floppy in MacOS native code. This is very fast (up to 1000x faster than a real 1541) but some games that use fast loaders or other special tricks of the 1541 will crash as this emulation does not support every single feature of a real 1541. On the other hand you can choose a complete floppy emulation, that will support most of the these games. Unfortunately this complete emulation also emulates the original speed of a 1541 of only about 256 Bytes/second. To switch between these two mode choose Devices/Disk Drive #(8/9)/Complete Floppy 1541 Emulation. Note that the complete emulation is only available on drives 8 and 9 and can only be used with D64, X64, G41 or ZipCoded files, but not with T64 or Lynx files nor Mac Folders that are mounted as floppy disks (see below).
G41 disk images offer maximal precision in emulation. Several tricks that can not be emulated with a D64 image are possible with a G41 image. Since G41 images are about twice as large as D64 images they should be (and are) only used when these tricks are really needed. Therefore G41 disk images almost always require Complete Floppy Emulation. Power64 does therefore automatically enable this feature for any drive that contains a G41 image.
The Complete Floppy Emulation is only available for the 1541 floppy disk drives. The 1571 and 1581 floppy disk drive can be emulated by Power64 only with the fast emulation method. This should generally not cause any problems, since C64 programmers did not exploit these drives with the same extreme scrutiny as they did with the 1541. Thus the fast emulation is usually sufficient.
Furthermore it is possible to use a folder on the Macintosh hard disk, as a floppy disk for the C64 and use games in C64 program format (P00, PRG, C64, CBM - see Appendix E.1/E.2). To make a Macintosh folder simulate a floppy disk drive choose: Devices/Disk Drive #x/Attach Hard Disk. Now the Macintosh folder behaves just like a C64 floppy disk. Of course the C64 was not designed with such an option in mind, and some C64-programs, that are tightly coupled with the floppy disk drive, won't run from hard disk. The hard disk will only perform the most basic floppy commands like LOAD/SAVE or OPEN, but none of the fancy floppy commands (like SCRATCH). This is done on purpose, to make sure that no C64 program can cause serious damage to the Mac hard disk.
Storing lots of C64 program in a single Mac folder tends to create clutter that is hard to keep track of. Furthermore it wastes hard disk space, since every single file requires at least one allocation block (often ≥ 32 KByte on large disks or CD-ROMs) on the Mac hard disk. To make things easier to manage it is possible to pack all those files into one neat ZIP archive, saving disk space and avoiding clutter.
To use a ZIP archive choose Devices/Disk Drive #x/Attach ZIP Archive. Now you can load and run games just like from a folder on your Mac hard disk. Note that you can only read from a ZIP archive - writing is not possible.
It is also possible to mount a T64 tape or Lynx file (see Appendix E.8/E.9 for a description of the file formats) on a disk drive by choosing Devices/ Disk Drive #x/ Mount Tape/Lynx. As with the Mac hard disk only a selection of commands is available.
Also it might seem queer to mount a tape in a disk drive some of the T64 and especially Lynx files that are available on the internet expect to be used on a disk drive.
To emulate the Datasette tape drive Power64 uses T64 and Lynx files (see Appendix E.8/E.9). To 'insert' a T64 or Lynx file in the virtual tape drive select Devices/Tape Drive/Mount Tape. Just as with Floppy Disk there is an option to create a blank tape image (Devices/Tape Drive/ Create New Tape) and to display the contents of a T64 or Lynx file (Devices/Tape Drive/Display Directory). Note that the file size in a tape directory is give in Bytes rather than Blocks.
In addition to T64 and Lynx files, Power64 can mount raw tape images using the TAP format (see Appendix E.10) on the tape drive (but not the disk drives). TAP files are highly precise representations of the contents of a C64 data tape and can contain data not only in the normal C64 format as it is read and written by routines in the C64 ROM, but also data in special formats that can only be read with the appropriate fastloader. This makes it impossible for Power64 to completely decode the data and transfer it to the C64 RAM at once. Instead it is necessary to run the fastloader on the emulated C64. This makes reading TAP images very slow. Data available in the normal C64 format are available at 50 byte/second, but are understood by Power64 and transfered instantly. Turboload data can be read at 200-500 byte/second (depending on the turbo load algorithm used), so that loading an average game will take several minutes. Usually a TAP image contains not only C64 and Turboload data, but also a generous amount of empty space. Use Power64's Turbo Boost mode (Options/Turbo Boost - Cmd-B) to accelerate the emulated C64 while loading.
To keep an eye on the floppy disk (and hard disk) activity of a C64 select Devices/Drive Status LEDs (Cmd-L; Use Opt-Cmd-L to display the LEDs in all C64 windows). This will cause Power64 to display two symbols per enabled disk drive in the bottom left corner. The first symbols stands for the floppy LED. If it is off (gray) the floppy drive is idle. A green LED indicates a read access, a red LED a write access and a yellow LED stands of an open file without read or write activity. The second symbol indicates the floppy error status; a green check means Ok, a red cross indicates an error. To determine the nature of the error, look at the bottom of the corresponding directory window. You can also use the following sequence of BASIC commands.
10 OPEN 1,8,15
20 INPUT#1, EN$, ER$, TR$, SC$
30 CLOSE 1
40 PRINT EN$, ER$, TR$, SC$
If Complete Floppy 1541 emulation is selected Power64 also displays the track that the floppy head currently uses in the bottom row of the directory window. As loading a file can take quite a while in this emulation mode, it is always reassuring to see the head move from track to track once in a while to know that something is happening.
Power64 offers versatile tools for manipulating C64 files, making it easy to convert between the different file formats or to create a custom compilation of favorite games.
To create a new disk select Devices/Disk Drive #x/Create New Floppy Disk. This new disk is already formatted, thus it is not necessary to issue a NEW (format) command before using the disk.
Similarly a new tape can be created using Devices/Tape Drive/Create New Tape.
To copy files between two disks or tapes, mount both source and destination on drives of a C64 and display the directories. Then select the files you want to copy with the mouse (use shift click to select ranges of files, and option-click to add/remove single files from your selection) and then drag your selection to the destination drive. You can also copy files from/to directory windows of the Finder.
To create a backup of a file on the same disk or tape hold down the option key while dragging the files out of the directory window and back again.
To delete files, select them as above and drag them to the Finder's trash can. Of course items in the trash can be recovered just as usual.
To rename a file, click on the filename (not on the file size, file type or the space in between) and leave the mouse there. After a short time, the filename will become editable. Please note that the new filename must contain only C64 characters.
It is also easily possible to switch disk/tape images and/or move to a different folder on the Mac hard disk. Click on ".." to mount the Mac Folder containing the currently mounted D64/T64 image as a C64 hard disk, or to move the the parent folder of the currently mounted Mac folder. Click on a D64/T64 in the currently mounted Mac folder to mount this disk/tape image. You can also use this method to navigate the subdirectories of a 1581 floppy disk image. Note that this approach to file navigation is not available, if full 1541 emulation is enabled.
In order to ensure consistency for the disk/tape images, Power64 prohibits modifications on devices that are in use by a C64-program (i.e. files are open), or when full 1541 emulation is enabled (making it impossible to tell if files are open).
Due to the unstructured content of a raw tape image, it is not possible to use the above methods for managing the files stored on TAP images.
Power64 provides the possibility to save the current state of the C64 to a Macintosh file. Thus it is easy to interrupt a game at any point, save it to disk, try the next level and if it was not successful then simply restore to the saved position.
Note that while this feature is called a RAM image, it also saves the contents of the CPU registers and the state of the VIC, SID and CIAs. Furthermore it saves the contents of the REU (if present) and the state of all completely emulated 1541 disk drives. Furthermore the tapes and disks that were attached are recovered, if they are again available on the computer. For reasons of Mac disk space efficiency the disks/tapes do not become part of the RAM image.
To create a RAM Image, select File/Save RAM Image (Cmd-S). To restore it choose File/Load RAM Image (Cmd-O). Note that a new emulator window will automatically be created for the loaded RAM image. Thus it is not necessary to open a new window before loading a RAM image, and it is impossible to destroy the contents of any other currently open window.
Power64 can also be used as a screen saver. Use it to run old C64 demos while your Mac is idle or have it display images of C64 game covers and old Commodore ads. Using File/Screen Saver it is possible to choose a delay after that Power64 goes to screen saver mode and choose if Power64 should run demos from RAM images and/or should show GIF/JPEG images, and pick folders from where these should come from. It is also possible to have Power64 change the displayed motive every so often.
Power64 Homepage: http://www.infinite-loop.at and http://www.salto.at - EMail:
© Roland Lieger, Goethegasse 39, A-2340 Mödling, Austria - Europe
Last Changed: Feb. 29, 2008