rob@wilbur.coyote.trw.com (Robert Heiss) (02/10/91)
How fast is one of the new 68300-series embedded CPU cores on 32 bit integer code? At 16 MHz with a DRAM memory system, would it be closer to a 68000 or a 68020? -Robert Heiss rob@wilbur.coyote.trw.com
mslater@cup.portal.com (Michael Z Slater) (02/11/91)
>How fast is one of the new 68300-series embedded CPU cores on >32 bit integer code? At 16 MHz with a DRAM memory system, would >it be closer to a 68000 or a 68020? Moto says the 68300 parts perform at about 80% of a 68020 at the same clock rate. It's not clear what assumptions are behind, this though. It does assume zero-wait-state memory on the 68300 part; I'm not sure what the memory assumption is on the 68020. It will also vary with the application, as always. Programs will small loops will benefit from the 68020's small I-cache, and the multibit shifts are slower on the 68300 parts, which might affect some programs considerably. My gut feel is that with comparable memory systems and the same clock rate, a 68300 part would be closer to an 020 than to a 68000, but may fall short of Moto's 80% estimate. Michael Slater, Microprocessor Report mslater@cup.portal.com