mos_8502 :verified: on Nostr: For those who aren't deeply familiar with the intricacies of retro CPUs: MHz is a ...
For those who aren't deeply familiar with the intricacies of retro CPUs:
MHz is a great measure of relative performance within a specific architecture -- a 4MHz 65C02 is, indeed, about four times faster than a 1MHz 65C02. But it's a *terrible* measure of relative performance *between* architectures, simply because different CPUs have different opcodes, which operate in different amounts of time. They're different in more than just mnemonics. A 1MHz 65C02 is *faster* than a 4MHz Z80 at the same tasks, because the 65C02 is much more efficient (though the Z80 is a fine CPU with many things to recommend it!).
So where does Sentinel 65X fit into this? We have an 8MHz W65C265S CPU, which is somewhere between a microcontroller and a SoC type of thing. In terms of CPU, it's cycle-and-opcode equivalent to a W65C816S at the same speed.
The W65C816S is a 16-bit CPU with an 8-bit data bus. This means that 16-bit reads and writes take one cycle more than 8-bit ones -- which is still much, much faster than a W65C02S can move data at the same MHz, because it does with one instruction what takes multiple ones on the W65C02S.
The opcodes which are shared between the '816 and the '02 run in the same number of cycles, but the additional opcodes of the '816 mean that it is 11 times faster at 16-bit maths, for example. Combined with the linear memory address space, free of bank switching, Sentinel 65X will equal or outperform the Commander X16 in every benchmark.
At 8MHz, Sentinel 65X is about 88 times faster than a C64 at 16-bit maths.
In terms of "benchmark" speed, when comparing tasks they are both suited to, the '816 runs rings around the Motorola 68000 in most respects at the same MHz clock speed.
At 8MHz, you are looking at the equivalent performance of, roughly speaking, about a 14MHz 68K, or a 20+MHz 80286. We have over twice the CPU performance of the Super Nintendo/Super Famicom, superior CPU performance to the Sega Genesis/Mega Drive, and even in the prototype *vastly* more available RAM (and four times that in the production version!).
In gaming muscle terms, we will be positioned solidly in between the SNES and the Neo•Geo.
The VERA is wildly more powerful than the VIC-II, as well. Dedicated internal VRAM, RGB output, 80x60, 80x30, and 40x30 character colour text modes, 128 hardware sprites (with the possibility of using the same multiplexing techniques as the C64 to get many times that!), multiple layers, hardware scrolling, 16-channel PSG sound and PCM sample playback, 256 colours from a palette of 4,096. If you like programming games in the style of mid-1990s 16-bit console games, this will please you greatly.
#Sentinel65X
MHz is a great measure of relative performance within a specific architecture -- a 4MHz 65C02 is, indeed, about four times faster than a 1MHz 65C02. But it's a *terrible* measure of relative performance *between* architectures, simply because different CPUs have different opcodes, which operate in different amounts of time. They're different in more than just mnemonics. A 1MHz 65C02 is *faster* than a 4MHz Z80 at the same tasks, because the 65C02 is much more efficient (though the Z80 is a fine CPU with many things to recommend it!).
So where does Sentinel 65X fit into this? We have an 8MHz W65C265S CPU, which is somewhere between a microcontroller and a SoC type of thing. In terms of CPU, it's cycle-and-opcode equivalent to a W65C816S at the same speed.
The W65C816S is a 16-bit CPU with an 8-bit data bus. This means that 16-bit reads and writes take one cycle more than 8-bit ones -- which is still much, much faster than a W65C02S can move data at the same MHz, because it does with one instruction what takes multiple ones on the W65C02S.
The opcodes which are shared between the '816 and the '02 run in the same number of cycles, but the additional opcodes of the '816 mean that it is 11 times faster at 16-bit maths, for example. Combined with the linear memory address space, free of bank switching, Sentinel 65X will equal or outperform the Commander X16 in every benchmark.
At 8MHz, Sentinel 65X is about 88 times faster than a C64 at 16-bit maths.
In terms of "benchmark" speed, when comparing tasks they are both suited to, the '816 runs rings around the Motorola 68000 in most respects at the same MHz clock speed.
At 8MHz, you are looking at the equivalent performance of, roughly speaking, about a 14MHz 68K, or a 20+MHz 80286. We have over twice the CPU performance of the Super Nintendo/Super Famicom, superior CPU performance to the Sega Genesis/Mega Drive, and even in the prototype *vastly* more available RAM (and four times that in the production version!).
In gaming muscle terms, we will be positioned solidly in between the SNES and the Neo•Geo.
The VERA is wildly more powerful than the VIC-II, as well. Dedicated internal VRAM, RGB output, 80x60, 80x30, and 40x30 character colour text modes, 128 hardware sprites (with the possibility of using the same multiplexing techniques as the C64 to get many times that!), multiple layers, hardware scrolling, 16-channel PSG sound and PCM sample playback, 256 colours from a palette of 4,096. If you like programming games in the style of mid-1990s 16-bit console games, this will please you greatly.
#Sentinel65X