3 ms·
At a disadvantage (2011) – Which was faster, an IBM PC or a Commodore 64?
- qwery 3y agoIn the Game Boy, the CPU is (broadly speaking) an 8080 derivative[0] running at ~4MHz. But all of the instructions take multiples of 4 cycles to execute, so when discussing clock cycles on the Game Boy, (homebrew) developers generally talk in units of four. That is, the CPU is considered (to the programmer) to be running at 1MHz. Note that that's an 8080 -- not an 8088, but I mention this because of the point in the article: > effectively turning the IBM PC from a 4.77MHz computer into a 1.1925MHz computer. [0] The SM83 CPU core, made by Sharp, is often viewed as something in between an 8080 and a Z80.
- aappleby 3y agoThe Game Boy also does stuff on both edges of the clock, so it's more like an 8-phase, 1 Mhz clock. Source - I wrote GateBoy.
- fuzzfactor 3y agoAlso the Commodore did not boot, it just started right up. The PC started much slower, especially since they had to boot to a disk of some kind, definitely a slow 5.25 inch floppy on the first PC which is when Commodore was already well-established. PC's also had no audio, color, or graphics, only internal beeper tones and monochrome text.
- Tuna-Fish 3y agoEverything after the startup loaded so much slower on the C64, though. Tramiel cheaped out on the disk controller, and the 64 had the worst floppy drive in the business.
- caf 3y agoThis feels like programming an 8088 like it's a 6502. The 8088 has a lot more general purpose registers than the 6502, so variables would tend to be kept in registers while they were being worked on. The encoding for ROR reg, 1 is only 2 bytes - so 4 cycles for instruction fetch, then another 2 cycles to execute.