
Chapter 5
Signal Descriptions
109
23542A/0—September 2000
AMD-K6-2E+ Embedded Processor Data Sheet
Preliminary Information
The processor always floats DP[7:0] except when they are being
driven during a write cycle as described above. In addition,
DP[7:0] are floated off the clock edge that BOFF # is sampled
asserted and off the clock edge that the processor asserts
HLDA in recognition of HOLD.
5.20
EADS# (External Address Strobe)
Pin Attribute
Input
Summary
System logic asserts EADS # during a cache inquire cycle to
indicate that the address bus contains a valid address. EADS#
can only be driven after the system logic has taken control of
the address bus by asserting AHOLD or BOFF # or by receiving
HLDA. The processor responds to the sampling of EADS # and
the address bus by driving HIT#, which indicates if the inquired
cache line exists in the processor’s caches, and HITM #, which
indicates if it is in the modified state.
Sampled
If AHOLD or BOFF # is asserted by the system logic in order to
execute a cache inquire cycle, the processor begins sampling
EADS # two clock edges after AHOLD or BOFF # is sampled
asserted. If the system logic asserts HOLD in order to execute a
cache inquire cycle, the processor begins sampling EADS# two
clock edges after the clock edge HLDA is asserted by the
processor.
EADS# is ignored during the following conditions:
s
One clock edge after the clock edge on which EADS# is
sampled asserted
s
Two clock edges after the clock edge on which ADS# is
asserted
s
When the processor is driving the address bus
s
When the processor asserts HITM#