Rapidus (available for both XL and XE computers) provides a 20MHz WDC 65C816 CPU, 14MB of linear RAM, 1024KB of fast SRAM, 512KB of flash ROM, DMA controller, on-board 65C816 OS, and more. To complement Rapidus (or any compatible 65C816 accelerator board) when used with Ultimate 1MB or Incognito, the Rapidisk driver improves hard disk bandwidth by up to a factor of three by running sector transfer code (which normally resides in ROM running at 1.79MHz) in high RAM, allowing transmission to occur at fully accelerated speeds. 

In addition to improving hard disk performance at higher clock speeds, Rapidisk provides a 24-bit sector buffer address, enabling direct transfer of data at any location in the 65C816’s address space. This works with IO on APT partitions and mounted ATR disk images.

Driver requirements:

  • Ultimate 1MB with SIDE2 or XEL-CF; Incognito
  • 65C816 accelerator board (Rapidus or compatible)
  • DracOS 65C816 OS