Ronald G Minnich wrote:
> We now have a pretty good boot picture on VIA mainboards with: 8601 north
> +686A south, or 8601 north +8231 south. No VGA yet, just serial console.
> Also, SPD is in but SDRAM really only works with one DIMM, until we get
> particulars of how to program this chipset registers for SDRAM. It's a
> little complicated.
> The only commercial products I've found with these chipsets are Compaq
> laptops. But if you want to try to find a mainboard with these parts, they
> both boot to multiuser. I know some people on this list indicated interest
> in these chipsets.
>
> ron
>
Yes ... I am using the VIA VT82C694X northbridge (ASUS P3V4X motherboard)
this chip is very similar to the 8601 northbridge. I haven't tried
initializing more than one DIMM yet so can't tell you whether the code works
with multiple DIMM's. I will be very interested in anything you learn from Via
about the art of setting up SDRAM.
SPD/SMBus trouble
We discussed this a while ago and you suggested debugging the code in user
mode which I did. The SMBus code seems to work fine but the SDRAM doesn't
respond at the address that it should. (the DIMM's do have a serial eeprom on
them!) I know that the code works because I connected the SMBus from the
motherboard under test to another motherboard which was up and running with
the same SDRAM DIMM's in and could talk to the serial eeproms across the link
to the other motherboard. So I know that the code is producing the right
signals on the SMBus and that the DIMM's do respond. I also know that the
board can't change the address of the serial eeproms as this is fixed (except
for the lower 3 bits of the address). All I can presume is that the SMBus on
this motherboard has branches on it which are addressed in a different way.
Has anyone come across anything like this?
Regards
Marcus Bigault
