GPIO as JTAG for FPGA

Hi Ran,

You need to refer FPGA reference manual for that firmware downloading.

You can use JTAG for downloading FPGA image file into h/w.

www.embedded.com/.../FPGA-programming-step-by-step

Hi Titusrathinaraj,

It is not that I try to do fpga programming using jtag.
We need to program the fpga not through the jtag bus, but through some GPIOs which were chosen for that purpose.
These GPIOs need to emulate jtag.
It seems that the above link contain driver which is supposed to do this, becuase it says: "Interface to JTAG must be provided from main device module,
for example through cx23885 GPIO".

Do you have any idea how to interface some GPIOs with such driver ?

Thank you,
Ran

Ran,

GPIO to FPGA communication is for very slow speed/bandwidth.

See if the below e2e threads will be in help:

e2e.ti.com/.../131886
e2e.ti.com/.../236075
e2e.ti.com/.../397887
e2e.ti.com/.../337589
e2e.ti.com/.../206956

Regards,
Pavel

Hi Pavel,

Thanks a lot for the links.
I walked through them, but I did not find yet a clue for my problem.

I did find the link in http://e2e.ti.com/support/arm/sitara_arm/f/791/t/337589 as maybe a way to program the flash, but I wander if that method really worked eventually.

I need to use the dedictaed GPIOs only for programming of the FPGA. This GPIOs should be used as jtag connector to FPGA.
How can I define GPIOs as jtag ?

Thanks,
Ran

Hi,

One more...
Are you familiar with some simple example or open source for programming FPGA with GPIOs ?

Thanks you,
Ran