Re: [f-cpu] No latches, please !

[Ben Franchuk <bfranchuk@jetnet.ab.ca>]

Juergen Goeritz wrote:
> Usually you only use latches to synchonize input signals
> to keep input setup times of other circuitry.

With a single phase clock found in modern designs you don't have the
non-overlaping clock needed by a latch. Older CPU's like the 6800,6502
used latches internally and needed a two phase clock. With my cpu I use
a 4x clock like 6809 to give me a clean memory interface. Internally I
could use latches or flip/flops for storage but use flip/flops because
of a slightly cleaner design. Some FPGA configurations favor latches
over flip/flops.
-- 
Ben Franchuk - Dawn * 12/24 bit cpu *
www.jetnet.ab.ca/users/bfranchuk/index.html
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