fastboot1541, an autostart fastloader for the Commodore 64 and 1541 that fits into a single sector.
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README.md
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README.md

fastboot1541

fastboot1541 is an autostart fastloader for the Commodore 64 and 1541 that fits into a single sector.

Use

This is the fastest way to chain-load a second-stage high-speed fastloader, since it only transfers about half a sector worth of data using the slow serial protocol, yet loads the next stage at ~10x speed - and it's an autostart!

Some Details

  • The file overwrites stack addresses to gain execution, which should make it compatible with most ROM modifications and cartridges.
  • The C64 part sits just above the stack.
  • The 1541 part executes in-place in the buffer that was written when loading the program for the C64.
  • The C64 and the 1541 part contain a simple bus protocol speeder that allows the screen to be on.
  • You should hand-edit the second byte of the resulting sector on disk so that only the C64-specific bytes are actually transfered.
  • Put this sector on track 18 to save some more time.
  • Choose the optimal interleave for the chainloaded data. Maybe you can fit it on track 18 as well.

More Details

The blog post at pagetable.com/?p=568 explains everything in detail.

License

Do anything you want with it, but giving credit and emailing me about its use is very much appreciated.

Improvements and corrections welcome!

Author

Michael Steil mist64@mac.com