README.MPC866 834 B

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  1. The current implementation allows the user to specify the desired CPU
  2. clock value, in MHz, via an environment variable "cpuclk".
  3. Three compile-time constants are used:
  4. CFG_866_OSCCLK - input quartz clock
  5. CFG_866_CPUCLK_MIN - minimum allowed CPU clock
  6. CFG_866_CPUCLK_MAX - maximum allowed CPU clock
  7. CFG_866_CPUCLK_DEFAULT - default CPU clock value
  8. If the "cpuclk" environment variable value is within the CPUCLK_MIN /
  9. CPUCLK_MAX limits, the specified value is used. Otherwise, the
  10. default CPU clock value is set.
  11. Please note that for now the new clock-handling code has been enabled
  12. for the TQM866M board only, even though it should be pretty much
  13. common for other MPC859 / MPC866 based boards also. Our intention
  14. here was to move in small steps and not to break the existing code
  15. for other boards.