High Performance Two Port 10/100 Managed Ethernet Switch with 32-Bit Non-PCI CPU Interface

Datasheet

8.4.8PIO Writes

PIO writes are used for all LAN9312 write cycles. PIO writes can be performed using Chip Select (nCS) or Write Enable (nWR). A PIO write cycle begins when both nCS and nWR are asserted. The cycle ends when either or both nCS and nWR are de-asserted. Either or both of these control signals must de-assert between cycles for the period specified in Table 15.12, “PIO Write Cycle Timing Values,” on page 450. They may be asserted and de-asserted in any order. Either or both of these control signals must be de-asserted between cycles for the period specified. The PIO write cycle is illustrated in the functional timing diagram in Figure 8.7.

The END_SEL signal has the same timing characteristics as the address lines.

Please refer to Section 15.5.8, "PIO Write Cycle Timing," on page 450 for the AC timing specifications for PIO write operations.

END_SEL

 

 

VALID

 

A[x:2]

 

 

 

 

 

 

 

 

VALID

 

nCS, nWR

 

 

 

 

 

 

 

 

 

 

 

 

D[31:0] (INPUT)

 

 

 

 

 

 

 

 

 

VALID

 

Figure 8.7 Functional Timing for PIO Write Operation

Revision 1.4 (08-19-08)

110

SMSC LAN9312

 

DATASHEET