There are lots of ARM versions, just as there are lots of 805x versions. However, ARM is MUCH faster, in terms of its instruction cycle.

The basic 805x lumbers along at somewhat less than 1 MIPS, and the fastest of them perhaps approaching 70 MIPS with a "typcial" instruction mix.

The really cheap ARM's operate at on the order of 50 MIPS, and the fastest I've worked with ran at 150 MIPS, that being > three years ago.

The ARM's with which I've had contact lived in TQFP-208 packages and attached directly to external SDRAM, FLASH, and SRAM memory, without which they couldn't do a thing.

805x's have internal ROM, RAM, and I/O, which enables them to do lots of things, particularly byte-processing things, without any external components, aside, perhaps, from their oscillator/clock. Clearly, they were designed with totally different visions of how they'd be used.

Now that there are ARM-based single-chip MCU's, about which I freely admit I still know absolutely nothing, I certainly will have to "give 'em a look" before selecting my next MCU. I've already given the ARM consideration in applications where external memory was required, since so many of them provide SDRAM and FLASH interfaces which are trivially implementable from the designer's viewpoint. This is because a $7 CPU with a $2 SDRAM and a $3 FLASH memory will cost less than a fast 805x with an external SRAM and an external code memory, including the latches and logic required, once the external memory size reaches a certain point.

I don't think there's any argument as to whether the ARM is easier to code than an 805x. You just simply have lots more flexibility with the ARM.

I still like the 805x, myself, though.

RE