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- THE TRUE CLOCKS OF THE MC68040
-
- Just a little demonstration with a FALCON, an AFTERBURNER 040, and
- GEMBENCH 4.03 with the INTEGER DIV test which consists of DIVU.W dx,dx.
- We read the timings for this DIVU in the Motorola DATABOOK of the 030
- and the 040.
- For the 030 : 44 clock cycles.
- For the 040 : 27 clock cycles.
- We launch GEMBENCH 4.03 and the INTEGER DIV test (ref. FALCON) on:
- FALCON STANDARD 16 MHz : 100 % (normal !).
- FALCON + AB040 32 MHz : 312 % (414 % at 40 MHz).
-
- Here is the equation, no comment.
- 68040 at 32 MHz = (44/27) x (32/16) = 3.26 or 326 %
-
- On the one hand, we have the theory with the DATABOOK (if some people
- want to interpret the DATABOOK differently, we ARE LISTENING !) which
- gives 326 and on the other hand, a real test on a machine which gives
- 312 !
- So, the hypothesis for the 040 at 32 MHz is proven correct.
- If the 040 was at 64 MHz, like some people would like us to believe,
- the gembench test should have been closer to :
-
- 652 = (44/27 x (64/16) !
-
- CENTEK
-