4

Universe (VMEbus to PCI) Chip

Table 4-2. Universe Register Map (Continued)

Offset

Register

Name

 

 

 

FF0

VME CR/CSR Reserved

 

 

 

 

FF4

VMEbus CSR Bit Clear Register

VCSR_CLR

 

 

 

FF8

VMEbus CSR Bit Set Register

VCSR_SET

 

 

 

FFC

VMEbus CSR Base Address Register

VCSR_BS

 

 

 

Register space marked as “Reserved” should not be overwritten.

!Unimplemented registers return a value of 0 on reads; writes complete Caution normally.

Note The VMEbus CSR Bit Clear Register and the VMEbus CSR Bit Set Register are not supported on the MVME2300. Writing a 1 to the VMEbus CSR Bit Set Register reset bit will cause the board to go into a permanent reset condition.

Universe Chip Problems after PCI Reset

Customers who overwrite the firmware settings for the Universe chip, or who replace the MCG firmware with their own, may find that under the conditions described below, there are problems with the Universe chip after a PCI reset.

Description

The Universe chip is being enabled on the PCI bus after a PCI reset (the problem does not occur after a board reset or power up).

The Universe is causing the "bye" command to hang the system. The Universe Master Enable and Memory Enable in the PCI_CSR (Configuration Space register) are enabled, even before the PCI_BS register has been initialized. The symptoms can be alleviated by modifying the PCI probe list such that the Universe PCI configuration is done first.

4-14

Computer Group Literature Center Web Site

Page 238
Image 238
Motorola MVME2300 Series manual Universe Chip Problems after PCI Reset, Description