How is it that Verdex XL6P boards are using DDR2 SDRAM when the PXA270
only supports SDRAM?
There appears to be 256MB of DDR2 SDRAM fitted to the Verdex XL6P
motherboard populated in partion 0 of the 1GB memory mapping, which is,
according to the latest Marvell documentation, is not supported.
Without schematics it's rather difficult to figure out exactly what's
going on but, at a glance, there appears to be a number of issues:
1) The Micron devices have 8 banks whereas the PXA270 only supports 4
2) The minimum SDCLK for DDR2 SDRAM is 125MHz, whereas the PXA270 is
setup for 104MHz SDCLK
3) The MDMRS configuration used appears to use a DDR2 'reserved' value
for the 'Write-Recovery' field (000b)
A couple of questions spring to mind:
1) Are schematics available or must customers reverse engineer the
2) Is this a robust design or is it flying on a wing and a prayer?