PRELIMINARY

INFORMATION

XpressFlow-2020 Series –

SC220

Ethernet Switch Chipset

XpressFlow Engine

© 1998 Vertex Networks, Inc.

3

Rev. 4.5 – February

1999

1. PIN ASSIGNMENT

1.1

Logic Symbol

SC220

T_MODE

C_D[15:0]

C_CE#

C_WE#

C_CM#

C_EC#

C_MF#

C_FF#

Test Pin

S_D[31:0]

S_MSGEN#

S_EOF#

S_IRDY

S_TABT#

S_OVLD#

8

8

S_HPREQ#

S_REQ[8:1]#

S_GNT[8:1]#

S_CLK

P_D[31:0]

P_CS#

P_ADS#

P_RWC

P_RDY#

P_BS16#

P_INT

P_A[11:1]

P_RSTIN#

P_RSTOUT

P_CLK

L_D[31:0]

L_OE[3:0]#

L_ADSC#

L_CLK

L_A[18:2]

L_WE[3:0]#

L_BWE[3:0]#

4

4

4

Note:

The SC220 is pin compatible to the SC201 with only one exception:

The RSTOUT pin of SC201 is defined as a synchronous RESET output pin which follows the RSTIN input and re-synchronous with

P_CLK for meeting the 80386 timing requirement.

The RSTOUT pin for SC220 has a totally different function. It is no longer related with the RSTIN input. The RSTOUT is a watch-

dog output from SC220 to keep track of the active state of the host processor. Host processor needs to access the Keep

Alive register periodically to prevent the setting of the RSTOUT output. The RSTOUT output can be use as Reset input to

the host processor.