CPU #0

The CoCo 5 was imagined to be controlled by 4 - 6309 CPU's and a GPU , If it ever gets implemented it will most likely be via FPGA. The CPU#0 refers to a 6309 or Turbo9 core which will provide an executive supervisory function for the entire system.

This CPU will always run at 7.152 MHz and will address memory beyond 64K by one of two methods STANDARD or XSC mode.

The main functions of CPU#0 are to:

      1. Handle System Startup including initialization of CPU's #1,2 and 3 based on physical switches, NVRAM settings and initial hardware configuration.
      2. Handle all Keyboard Input allowing for keyboard buffering even when the destination CPU is halted and allow for Macros.
      3. Work with the GPU to handle all Screen Output.
      4. Handle hardware systems for Tri-CoCo Mode.
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