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System Memory Controller (SMC)
3
$FEF800D2
bit 3
(trp)
tRP
(SPD Byte
27)
tRP_CLK = tRP/T
(T = CLK Period
in nanoseconds)
See Notes 3, 4 and 9
0.0 < tRP_CLK <= 2 trp =%0
2.0 < tRP_CLK <= 3 trp =%1
3 < tRP_CLK Illegal
$FEF800D2
bit 7
(trcd)
tRCD
(SPD Byte
29)
tRCD_CLK = tRCD/T
(T = CLK Period
in nanoseconds)
See Notes 5, 6 and 9
0.0 < tRCD_CLK <= 2 trcd =%0
2.0 < tRCD_CLK <= 3 trcd =%1
3 < tRCD_CLK Illegal
$FEF800D0
bits 5,6,7
(trc)
tRC
(SPD Bytes
30 and 27)
tRC_CLK = (tRAS +
tRP)/T
(T = CLK Period
in nanoseconds)
See Notes 7, 8 and 9
0.0 < tRC_CLK <= 6.0 trc =%110
6.0 < tRC_CLK <= 7.0 trc =%111
7.0 < tRC_CLK <= 8.0 trc =%000
8.0 < tRC_CLK <= 9.0 trc =%001
9.0 < tRC_CLK <= 10.0 trc =%010
10.0 < tRC_CLK <=
11.0 trc =%011
11.0 < tRC_CLK illegal
Table 3-18. Deriving tras, trp, trcd and trc Control Bit Values from SPD Information (Continued)Control Bits Parameter Parameter Expressed
in CLK Periods Possible Control Bit Values