3

Table 3-6:

PLX PCI 6254 Configuration Signals

P M C / P C I I N T E R F A C E

Bridge EEPROM

.B.R.I.D. G. .E. .E.E. P. .R.O. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The PLX PCI 6254 PCI-to-PCI bridge utilizes ROM interface signals to initialize the PCI 6254 registers. The following table briefly describes these signals (see the data book for complete information):

Signal

Description:

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

EEPCLK

The EEPROM Clock output signal to the EEPROM interface is used during

 

autoload and for VPD functions. This pin is tri-stated if EE_EN* = 1.

 

 

EEPDATA

The EEPROM Serial Data interfaces to the EEPROM (bi-directional). This pin

 

is tri-stated if EE_EN* = 1.

 

 

EE_EN*

The EEPROM Enable LOW input enables EEPROM access.

 

0=enable EEPROM use

 

1=connect to logic 1 state

 

 

Register 3-2:

PCI6254 Configuration Registers– Transparent Mode

.P.C.I. .6.2. 5. .4. .C.O. .N.F. I.G. .U.R. A. .T.I .O.N. . R. .E.G. I.S. T. .E.R.S. . . . . . . . . . . . . .

The PCI 6254 can be configured to act as either a transparent or non-transparent PCI- to-PCI bridge by selecting the appropriate jumper on JP5 (see page 2 -9). In transparent mode, the CC1000dm system PCI bus is connected to the PCI 6254 primary port. The PCI 6254 non-transparent mode acts as a memory-mapped PCI device with the primary port connected to the cPCI backplane.

Primary

 

 

 

 

 

 

 

 

Offset

31

24

23

16

15

8

7

0

 

 

 

 

 

 

 

 

 

00h

 

Device ID

 

 

Vendor ID

 

 

 

 

 

 

 

04h

 

Primary Status

 

 

Primary Command

 

 

 

 

 

 

 

 

 

08h

 

 

Class Code

 

 

 

 

Revision ID

 

 

 

 

 

 

 

 

0Ch

 

BIST

Header Type

 

Primary Latency Time

 

Cache Line Size

10h

 

 

 

 

 

 

 

 

 

 

 

reserved

 

 

 

18h

Secondary Latency Timer

Subordinate Bus Number

Secondary Bus Number

 

Primary Bus Number

1Ch

 

 

 

 

 

 

 

 

 

Secondary Status

 

 

I/O Limit

 

I/O Base

20h

 

 

 

 

 

 

 

Memory Limit

 

 

Memory Base

24h

 

 

 

 

 

 

Prefetchable Memory Limit

 

 

Prefetchable Memory Base

 

 

 

 

 

 

 

 

 

3-6CC1000dm User’s Manual

10004281-02

Page 38
Image 38
Emerson CC1000DM user manual I.D. G. .E. .E.E. P. .R.O. M, Bridge Eeprom