====== MPU ======
Micro-Processor Unit

Motorola [[MC6809E]] :: The 8-bit beast of a microprocessor that punches far above its weight \\
Hitachi [[HD6309E]] :: The greatly expanded 6809E by Hitachi found to have many hidden features \\
[[Vectors]] :: Addresses for the various Interrupt Service Routines called by the processor during those events \\
[[Stacks]] :: The 6x09 supports two separate stacks in hardware - a System (S) stack and a User (U) stack \\
[[Interrupt]] :: The 6x09 microprocessors "stack" registers onto and off of the hardware stack (S) during a Interrupt Requests \\
[[Secondary Stack]] :: Additional stack used by Super Extended Basic high-resolution graphics commands\\

[[CPUID.cas]] :: A hybrid BASIC/assembly program to detect whether your CoCo has a 6809 or 6309 \\

===== CLOCKS =====

^ CLOCK CRYSTALS  ^ NTSC 60HZ ^ PAL 50HZ ^
| CoCo 3 Crystal Base MHz (315 / 11) | 28.63636 | 28.475 |
| CoCo 1/2 Crystal Base MHz (100 / 7) | 14.31818 | 14.23753 |

^ GIME-X TURBO  ^ NTSC 60HZ ^ PAL 50HZ ^
| GIME-X Turbo Hz | 2860000 | NA |
| MPU Clocks per Turbo field | 47666.66 | NA |
| MPU Clocks per Turbo scanline | 181.587 | NA |

^ SAM FAST ^ NTSC 60HZ ^ PAL 50HZ ^
| SAM Fast CPU Hz | 1789772.6825 | 1779687.5 |
| MPU Clocks per Fast field | 29829.54 | 35593.75 |
| MPU Clocks per Fast scanline | 113.63 | 113 |

^ SAM SLOW ^ NTSC 60HZ ^ PAL 50HZ ^
| SAM Slow CPU Hz | 894886.34375 | 889843.75 |
| MPU Clocks per Slow field | 14914.7 | 17796.875 |
| MPU Clocks per Slow scanline | 56.81 | 56.95 |

NTSC = 30 frames per second 525 scanlines of 2 fields per frame of 262.5 scanlines per field, interlaced.

PAL = 25 frames per second of 625 scanlines of 2 fields per frame of 312.5 scanlines per field, interlaced.

===== RTS =====
Return to [[:Tandy Color Computer:]]