chipscope pro and jtag

crazy things are fun, but in your case it want help :( xilinx uses kernel driver that bypasses IO virtualization, so request from chipscope are executed to hardware directly (executing at x86 ring 0) you can not intercept that.

choices are:

1 external hardware that wraps Xilinx Cable III to your hardware 2 internal PCI board that emulates a LPT device and Cable III and rewraps to you adapter 3 fake kernel driver that you use to replace xilinx driver, you need full disassembly and RE for that 4 fake communication DLL again full disassembly and RE needed. 5 intercept dll, it exposes xilinx DLL entry points and call xilinx dll (that you have renamed) part of the calls are re routed to your dll that then talks to your hardware 6 you install windows in BOCHS PC simulator, install chipscope in windows that runs in bochs, and you use customized BOCHS (rewrite and recompile!) to reroute the hardware access to your device.

FUN! antti

Hi Antti,

that sounds good to me.

I never thought of that way. Isn´t it possible to stack a filter onto xilinx kernel driver?

Do you know which Xilinx DLL I have to deal with? :-)

thomas

stupid, me, yes it would. its just that I havent written such drivers

not hard to find, check out whitch one talks the xpc4drvr.sys

antti

Hi to all interested in,

Xilinx support respondet, that in the future it will be possible to redirect the jtag signals to custom registers. The developer agreed that it is a very useful feature. Not only for us...

today, there is no way to make reuse of the parallel III / IV driver ...

thomas

"Antti Lukats" schrieb im Newsbeitrag news: snipped-for-privacy@posting.google.com...

xilinx

well the jtag signals can be used with custom registers today, no problems with that!!

you can reuse Cable III, no problems with that, just write your own logic analyzer core, write the custom registers, connect them to BSCAN primitive, and then use JAM player to talk to your custome logic analyzer and custom registers.

this cant be used with Cable IV, because the API and documentation about Cable IV are kept as secret.

antti

I have successfully used a Cable IV assuming it is a Cable III. The only problem is that iMPACT leaves the cable and your port in an undefined state, so you have to reset the ECP mode and reset the cable (reset printer). Of course you will not benefit from the ECP speed possible with the Cable IV.

Henk van Kampen

do you want to say that Cable IV is Cable III backward compatible in non-ECP mode?

if it so then it very good information antti

Yes, see also the datasheet of the IV cable. It says that the cable will go to 'compatability' mode if the ECP mode of your parallel port is not enabled. This compatability mode appears to be cable III functionality.

Henk van Kampen