Forums

SDRAM controller

Started by FP June 9, 2008
I am looking for a SDRAM controller for Xilinx Spartan3 device in
Verilog. xapp 134 has one which targets virtex 2 devices. Xilinx MIG
can be used for DDR and DDR2 SDRAMs. Can a DDR SDRAM controller be
used to drive SDR SDRAM?
What other options do I have?
FP <FPGA.unknown@gmail.com> wrote:

>I am looking for a SDRAM controller for Xilinx Spartan3 device in >Verilog. xapp 134 has one which targets virtex 2 devices. Xilinx MIG >can be used for DDR and DDR2 SDRAMs. Can a DDR SDRAM controller be >used to drive SDR SDRAM?
Yes, with some minor modifications this should be possible. But beware, there are no usefull free DDR controllers available for the Spartan3 series. -- Programmeren in Almere? E-mail naar nico@nctdevpuntnl (punt=.)
> I am looking for a SDRAM controller for Xilinx Spartan3 device in > Verilog. xapp 134 has one which targets virtex 2 devices. Xilinx MIG > can be used for DDR and DDR2 SDRAMs. Can a DDR SDRAM controller be > used to drive SDR SDRAM? > What other options do I have?
I need this SDRAM controller too. There are some on OpenCores, but with gotchas.
FP wrote:
> Can a DDR SDRAM controller be used to drive SDR SDRAM?
No, unless it is a combined DDR/SDR controller, and those aren't common.
> What other options do I have?
An SDR DRAM controller.
FP <FPGA.unknown@gmail.com> writes:

> I am looking for a SDRAM controller for Xilinx Spartan3 device in > Verilog. xapp 134 has one which targets virtex 2 devices. Xilinx MIG > can be used for DDR and DDR2 SDRAMs. Can a DDR SDRAM controller be > used to drive SDR SDRAM? > What other options do I have?
Write one? Assuming you have relatively modest performance requirements (which seems reasonabnle, or you'd be using DDR), it's not a huge task. My first significant piece of VHDl was an SDRAM controller, years ago using a FLEX10KE part! SDR is really not that complicated, and the timing is fairly easy for modern devices to handle. Cheers, Martin -- martin.j.thompson@trw.com TRW Conekt - Consultancy in Engineering, Knowledge and Technology http://www.conekt.net/electronics.html