AMD-762 Datasheet, PDF (103/122 Pages) Advanced Micro Devices – System Controller

24416C—December 2001
Preliminary Information
AMD-762™ System Controller Data Sheet
Table 34. Signal Descriptions (Continued)
Signal
Type
Description
ADSTB[1:0]
ADSTB[1:0]#
PIPE#
RBF#
WBF#
SBA[7:0]
SBSTB/SBSTB#
AGP-Only Signals
AGP AD Bus Strobe
B _{These signals are driven by the agent that is providing the data and are used to generate a}
STS timing strobe for 2x AGP transfers. ADSTB[0] is used for A_AD[15:00], and ADSTB[1] is
used for A_AD[31:16].
AGP AD Bus Strobe (4x Timing)
B _{These signals are driven by the agent that is providing the data, and are used to generate}
STS a timing strobe for 4x AGP transfers. ADSTB[0]# is used for A_AD[15:00], and ADSTB[1]#
is used for A_AD[31:16].
APG Pipelined Request
I This signal is asserted by the current master to indicate that a full-width request should be
STS
enqueued by the AMD-762™ system controller AGP target controller. The AMD-762
system controller enqueues a new request each edge of AGPCLK while the PIPE# signal is
asserted.
AGP Read Buffer Full
I ^{This signal indicates that the AGP master’s input buffer is full, and that it cannot accept}
more read data. When this signal is asserted by the AGP master, the AMD-762 system
controller does not attempt to return previously requested low-priority read data.
AGP Write Buffer Full
I ^{This signal indicates that the AGP master cannot accept more fast writes from the}
AMD-762 system controller. When this signal is asserted by the AGP master, the AMD-762
system controller does not attempt to initiate fast writes.
AGP Sideband Address Bus
I
These pins provide an additional bus that can be used to pass commands (address and
data) from the AGP master to the AMD-762 system controller. The sideband bus is driven
by an external AGP master.
AGP Sideband Strobes
I _{These strobes are driven by the AGP master to provide timing for the sideband address}
STS bus (SBA[7:0] pins). The SBSTB# pin provides the complement of SBSTB and is used only
for AGP 4x timing mode.
Chapter 7
Signal Descriptions
91