Target Board Information STMicroelectronics GX1 Eval (mb317)

GX1 Evaluation Board

General Information

This board has two major revisions, the Rev A and Rev B. The major difference between the two is that the A has SDRAM, whereas the B has DDR.

The board offers 5 PCI slots, 3 at 3.3V and 2 and 5V. The board has 64Megs on the LMI and 16 megs of flash.

Known problems with this board

• Audio DAC explodes

  Rev A only. If you plug the power supply connector in live, you will hear a bang and likely see a smoke column rising from the audio DAC. Don't worry. There is nothing to drive it on the GX anyway. If you want to avoid heart failure, we advise that you always use an external switch to switch on power to the board. The problem is caused by applying one power line before the other, the DAC doesn't like that.

• DDR and PCI problems on RevB

  RevB only. We have experienced problems using the DDR memory and the PCI bus at the same time. For this reason, we do not recommend using a RevB GX1 Eval and Linux.

• Missing pullups on Rev A PCI

Pullups are missing on the REQ,GNT lines so PCI card that require DMA will not function. These pullups must be added before using the board with Linux.

In additon a pullup is missing on the SERR signal of the secondary (5V) bus. Again this needs to be added.

• No -12V supply

  The lack of a -12V supply is not usually a problem, except for sound cards which require -12V for the analogue output stage.