
2-18
Signal Descriptions
Copyright 2000–2001 by LSI Logic Corporation. All rights reserved.
DSet0EnU, DSet1EnU, DSet2EnU, DSet3EnU
Data Set 0, 1, 2, 3 Upper Enable
Driving this signal HIGH enables the clock on the Set 0,
1, 2, or 3 Upper RAM. Driving it LOW disables the clock,
which saves power. The RAMs do not have to connect to
this pin. The function is not changed if the RAMs ignore
the enable and clock every cycle.
Output
DSet0LData[31:0], DSet1LData[31:0], DSet2LData[31:0],
DSet3LData[31:0]
Data Set 0, 1, 2, 3 Lower Data
This 32-bit bus contains data read from the lower data
cache Set 0, 1, 2, or 3 RAM.
Input
DSet0Tag[31:0],DSet1Tag[31:0], DSet2Tag[31:0], DSet3Tag[31:0]
Data Set 0, 1, 2, or 3 Tag
This 32-bit bus contains data read from the data cache
Set 0, 1, 2, or 3 Tag RAM.
Input
DSet0UData[31:0], DSet1UData[31:0], DSet2UData[31:0],
DSet3UData[31:0]
Data Set 0, 1, 2, 3 Upper Data
This 32-bit bus contains data read from the upper data
cache Set 0, 1, 2. or 3 RAM.
Input
DSet0We0L, DSet1We0L, DSet2We0L, DSet3We0L
Data Set 0, 1, 2, 3 Write Enable Byte 0, LowerOutput
Asserting this signal HIGH enables writing to data bits
[7:0] in the Lower RAM of data set 0, 1, 2, or 3.
DSet0We1L, DSet1We1L, DSet2We1L, DSet3We1L
Data Set 0, 1, 2, 3 Write Enable Byte 1, LowerOutput
Asserting this signal HIGH enables writing to data
bits [15:8] in the Lower RAM of data set 0, 1, 2, or 3.
DSet0We2L, DSet1We2L, DSet2We2L, DSet3We2L
Data Set 0, 1, 2, 3 Write Enable Byte 2, LowerOutput
Asserting this signal HIGH enables writing to data
bits [23:16] in the Lower RAM of data set 0, 1, 2, or 3.
DSet0We3L, DSet1We3L, DSet2We3L, DSet3We3L
Data Set 0, 1, 2, 3 Write Enable Byte 3, LowerOutput
Asserting this signal HIGH enables writing to data
bits [31:24] in the Lower RAM of data set 0, 1, 2, or 3.