Intel NETWORK PROCESSOR IXP2800 - Manual (Page 164)

164 Hardware Reference Manual
Intel
®
IXP2800 Network Processor
Intel XScale ® Core
Mode 4 Write Interface Protocol
Figure 54 depicts a single write transaction launched from the IXP2800 Network Processor to the
Intel and AMCC* SONET/SDH device, followed by two consecutive reads.
Compared with the Lucent* TDAT042G5, this device has a shorter access time, about eight clock
cycles (i.e., 120 ns). In this case, an intervened cycle may not be needed; therefore, the throughput
is about 12.5 Mbytes per second.
Figure 54. Mode 4 Single Write Transfer (B0)
B1756-04
SP_CLK
SP_ALE_L
SP_CS_L[1]/CSB
SP_WR_L/RWB
SP_RD_L/E
2 0 4 6 8 10 12 14 16 18
SP_AD[7:0]
SP_ACK_L/INT
SP_CP
SP_OE_L
A[10:1] A[10:1]
SP_DIR
ADDR[15:0]
DATA[15:0]
A
[15:8]
D
[7:0]
A
[7:0]
A
[15:8]
A
[7:0] D[15:8] D[7:0] D[15:8]
A
[7:0]
A
[7:0]
D[15:0] D[15:0] D[15:0] 2xD[15:8] D
[7:0]