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I got the dragon board and think its real nifty.

I just wanted to make some suggestions for later revisions. The copper pour around the solder pads is too close for comfort I think for hand soldering. The solder mask is good but maybe after several uses the pad might short.

Some of the VIA's around the solder pads that are next to the PCI pads are way too close. Might have to do some hand routing or better yet make the board bigger [vertically to keep its nice rectangular shape] so that theres room for traces.

Some of the 3.3's and GND are in weird spots of the vertical dual row header. Would be nice to have them at the end somewhere so you dont have to count over and over to make sure your on the right one.

Would it be practical to make the board longer so it can reach the PCI faceplate to secure it and then you can have the ethernet ports on the outside like a real NIC card? [or with a IDC cable coming out for those using the header along with the USB port]. Right now my 'puters got that skelator look with the sidecover off;)

Ive used several cybress ezusb devices and have there ezusb.sys installed. I had to manually install the dragon driver. Why not use their driver instead?

Lastly is there some way to trick the PCI controller so I dont have to load the PnP project file then reboot, cancel the hardware wizard then continue to load my own projects? Im only using it for IO and my bios doesnt have the '...PCI clk detect' option. Is there some way to implement only part of the configuration space without having full blown PnP functionallity requiring some windows driver? IOW whats the simplest way to enable the PCI clk?

Its a great board for PCI projects.

I know that the copper pour is tight... That makes a soldering job a little harder but has the advantage to give better signal integrity.

I have a new rev. of the board coming that is bigger horizontally ("longer"), but not vertically. I could make it bigger vertically but I like to be able to plug the board into a solderless breadboard, and if it's too big, it takes a lot of space on the breadboard.
I think that making the board so that the Ethernet reach the end of the PC is a good idea.

I tried to distribute the GND on the vertical header so that there is a GND connection close to every IO (good for high-speed signals), while still put as many IOs as possible. So it's a trade-off.

The Dragon USB driver has been improved compared to the ezusb one, that's why it's separate.

You don't have to reboot the PC to make the PC recognize the PnP space in the PCI. Go to the "Device manager" and click on the "Scan for hardware change" button. XP recognizes the new PnP changes.
If your PC doesn't have a BIOS option to enable the PCI clk, my guess is that it's always on.

Thanks for the feedback/suggestions.

Do you have the JTAG of the prom and spartan seperate for a reason?

Do you have the M0,1,2 pins pulled to ground so it uses master serial mode? I finally built me a board with spartan and a prom and used that mode but you cant program the FPGA by itself in the chain, even thought the doc's say that boundary scan mode over rides the setting of the Mode pins, it appears this isnt the case. Ill put a jumper on it 'next time' on M0 so you can change the mode.

no good reason.
The board uses the slave parallel mode (when data is coming from the USB) or master serial (when data is coming from the boot-PROM).

Note that the new revision of the board doesn't have a boot-PROM JTAG header anymore because the boot-PROM is now configured through USB - makes things simpler and faster.

How do you program the PROM with the usb on the new revision on the dragon? Cant that paticular prom only be programmed with JTAG interface?

Do you just manually control the TDx lines with a port on the ezusb and simulate a jtag stream?

I changed the PROM, it is not JTAG anymore but SPI, which is easier to control.
So in the latest rev., the USB cable can be used to program both the FPGA and the boot-PROM. I'm working on more stuff, like controlling the I2C and the 8051. I should have a new FPGAconf application ready soon with all that.

The latest FPGAconf allows to control the 8051 and I2C bus from the PC.