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Machine Cycle: Difference between revisions
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A '''Machine Cycle''' is one tick of the [[5A22]]. It may be configured to take 6, 8, or 12 [[master clock]] cycles. In the SNES scene, we call the 6:1 configuration [[fastROM]] and the 8:1 configuration [[slowROM]]. | A '''Machine Cycle''' is one tick of the [[5A22]]. It may be configured to take 6, 8, or 12 [[master clock]] cycles. In the SNES scene, we call the 6:1 configuration [[fastROM]] and the 8:1 configuration [[slowROM]]. The 5A22 decides which configuration to use depending on the address that is on the 65c816's address bus, and clocks the '816 clock input accordingly. | ||
Multiplication takes about 8 machine cycles and division takes about 16.<sup>[3]</sup> | Multiplication takes about 8 machine cycles and division takes about 16.<sup>[3]</sup> | ||
Latest revision as of 13:45, 21 October 2024
A Machine Cycle is one tick of the 5A22. It may be configured to take 6, 8, or 12 master clock cycles. In the SNES scene, we call the 6:1 configuration fastROM and the 8:1 configuration slowROM. The 5A22 decides which configuration to use depending on the address that is on the 65c816's address bus, and clocks the '816 clock input accordingly.
Multiplication takes about 8 machine cycles and division takes about 16.[3]
See Also
References
- last bullet point under 13.2 of page 2-13-1 of Book I of the official Super Nintendo development manual
- Figure 3-4-2 "Clear Timing" on page 3-4-1 of Book I, lbid.
- 15.2 Absolute Multiplication/Division on page 2-15-1 on Book I, lbid.
- https://ersanio.gitbook.io/assembly-for-the-snes/deep-dives/cycles