Hardware Reference Manual 165
Intel® IXP2800 Network Processor
Intel XScale® Core
Mode 4 Read Interface ProtocolFigure 55 shows a single read transaction launched from the IXP2800 Network Processor to the Intel and AMCC* SONET/SDH device, followed by two consecutive writes.Similarly, the access time is much better than the Lucent* TDAT042G5. The access time is about eight clock cycles or 160 ns. Here, we need an intervened cycle at the back. Therefore, the throughput is 11.2 Mbytes per second.Figure 55. Mode 4 Single Read Transfer (B0)
B1757-07
SP_CLK
SP_ALE_L
SP_CS_L[1]/CSB
SP_WR_L/RWB
SP_RD_L/E
20 4 6 8 10 12 14 16 18 20 22 24 26
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]
A
[7:0]
D[15:8] D[7:0]
A
[7:0]
D
[7:0]
A
[7:0]
D[15:0] D[15:0] 2xD[15:8]
A
[15:8]
A
[7:0]
D
[7:0]
A
[7:0]
D[15:8]
D[15:0]
D
[7:0]