Hi
I have built a parallel cable III and uses only resistors for protecting my lpt port.it can config my spartan II (xc2s200) device.now i have made a new board with XCF04S and xc3s400 device in jtag chain. when i start iMPACT it recognizes these devices but when i try to read devices id or doing something else it say's read faild and similar messages.does any body know how to solve the problem.
thanks in advance.
Maybe you have to setup the instruction register length (in number of bits) for each device somewhere?
i think it's because the speed of jtag is high and my cable gets noisy.do you know how to reduce the jtag clock speed
No, I don't. I only have experience with Altera and always had the luxury of being able to use official programmers.
Do you have some board that is guaranteed to work so you can rule out the programmer? Or scope the JTAG lines?
Hi
I have solved the problem.it was a small solder!
