AMD-K6 Datasheet, PDF (104/346 Pages) Advanced Micro Devices – AMD-K6 Processor

AMD-K6^® Processor Data Sheet
Preliminary Information
20695H/0—March 1998
5.9
Summary
Sampled
BF[2:0] (Bus Frequency)
Inputs, Internal Pullups
BF[2:0] determine the internal operating frequency of the
processor. The frequency of the CLK input signal is multiplied
internally by a ratio determined by the state of these signals as
defined in Table 13. BF[2:0] have weak internal pullups and
default to the 3.5 multiplier if left unconnected.
Table 13. Processor-to-Bus Clock Ratios
State of BF[2:0] Inputs
100b
101b
110b
111b
000b
001b
010b
011b
Processor-Clock to Bus-Clock Ratio
2.5x
3.0x
2.0x
3.5x
4.5x
5.0x
4.0x
5.5x
BF[2:0] are sampled during the falling transition of RESET.
They must meet a minimum setup time of 1.0 ms and a
minimum hold time of two clocks relative to the negation of
RESET.
86
Signal Descriptions
Chapter 5