Hi,all

I'm using cyclone ep1c12 to implement pci interface.Only bank1 and bank3 support pci io
standard,so i have to place the interface signals on those banks.While my device is PQFP240 i
find that it is very difficult to conform to the traces length constraints if the PCB has only
two layers.
Can anyone help me?
Regards
liqiyue

Hi Liqiyue, I found the same problem, if you use BGA package you then have enough pins in one bank, but with two layers is not possible to route all the tracks. ----- Original Message ----- From: "李奇越" liqiyue@ustc.edu> To: "pci" pci@opencores.org> Sent: Wednesday, March 31, 2004 1:59 PM Subject: [pci] pci route problem
support pci io

device is PQFP240 i

if the PCB has only

To Dave Warren

cyclone only supports 3.3v pci io,can i use it directly in a 5v pci signaling environment with pci clamping diode enabled?

I'm using an ACEX1K100 (only suports 3.3v) and it works fine. You don't
need to use the clamping diodes.

Sebastián Fernández

Hi liqiyue, My design is for an embedded processor card with PCI, I know both devices are only 3.3V. However if I had to protect the Cyclone FPGA against 5 volt signals I use a FET switch device. The power to the FET switch chip is taken from 5 volt through a power diode. The FET switch introduces no delay, but it goes high impedence as inputs approach it's supply voltage. This way Cyclone will never see high voltage. A suitable part is Fairchild FST3245 octal switch. It will not help your routing problems, but maybe you could use any IO's you want and could turn off the PCI clamp on the FPGA. By the way Sebastián Fernández is using an ACEX part which is safe for 5 volt, Cyclone is not! ----- Original Message ----- From: "李奇越" liqiyue@ustc.edu> To: "Discussion list about free, open" pci@opencores.org> Sent: Wednesday, March 31, 2004 3:22 PM Subject: Re: Re: [pci] pci route problem
signaling environment with pci clamping diode enabled?