Found a patent I'd mentioned previously - the one which Commodore owned, about implementing single-cycle opcodes.
"System for accelerating execution of program instructions by a microprocessor"
Issued 1992, inventors Gardei and Hauck.
BigEd wrote:
Looking at the
65ce02 datasheet (pdf) we see
Quote:
A unique design feature allows [Address registers] ADL and ADH to store indirect address vectors while [Address Counters] ABL and ABH function as counters, thus relieving the ALU from internal address fetches and increasing throughput
and we also see some additional busses in the block diagram (see below)
The same datasheet shows the reduced cycle counts, including many single-cycle instructions (and no page-crossing penalties). Garth has previously mentioned patents covering the elimination of dead cycles, but I haven't yet discovered the patent numbers.