From: Ron Lockwood-Childs <rlc2@ds...> - 2007-08-16 19:33:53
Quoting from the Verdex FAQ:
"Is support available for memory expansion and DMA transfers on verdex
Yes, there are SDRAM control signals on the 120-pin connector to enable
off-motherboard RAM expansion."
This is slightly misleading, as I read this as two different questions:
A) Can the verdex control external memory
B) Can an external device master the Verdex memory bus for doing DMA
The answer only really answers A). For our application we really need
B). Unfortunately we have already built a circuit board with an FPGA
that we've intended for accessing the SDRAM on the Verdex (this IS
theoretically possible, see the PXA270 CPU developer manual, section
6.4.6). The appropriate signals seemed to be available from the 120-pin
molex connector, only now did we discover that the SDRAM chip select
line, SDCS0, is not.
My question is, is there some way for us to jumper this signal onto our
daughterboard from the Verdex motherboard (or even connect it to a GPIO,
which would be ideal), or will we need to order customized Verdex boards
VCT Labs, Inc.