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 6×09 supports two separate stacks in hardware - a System (S) stack and a User (U) stack
Interrupt :: The 6×09 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
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