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Old 17 August 2012, 18:32   #148
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Originally Posted by Schoenfeld View Post
Really? The way I'm reading the datasheet is that STERM is sampled on the next half-clock after AS, and the cycle can be completed on the half-cycle after that, so the total time after AS would be a single cycle.

If you count from ECS, this would be 1.5 cycles. Either way, it's a full cycle less than the fastest access that I have done before. ACA1231 beats the crap out of the B1230-IV, despite almost 20% lower clock rate. So much for "on-chip cache hit rate of the 68030".

Yes, but AS is asserted 1/2 clock after the cycle begins unless a cache hit causes the 68030 to abort the external cycle! So it's 1.5 clocks from AS or 2 clocks from ECS. With your 2x clocked SDRAM I would be surprised if you didn't beat the crap out of any older DRAM based design operating at similar (68030) clock speeds.
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