cancel
Showing results for 
Search instead for 
Did you mean: 
Highlighted
Anonymous
Not applicable
12,785 Views

FX2 Micrcontroller JTAG FPGA configuration

Hello,

 

i am looking at various options to configure a Spartan3E(XC3S500E) part. This device would connect to a PC via Cypress(FX2) USB controller and would boot off a SPI flash(M25P40 Boot Prom).  Initially,I would like to program the bitstream directly to the FPGA using its JTAG pins. Ideally this would be accomplished by using the FX2 to bit-bang the FPGA JTAG pins . Once,the default configuration is loaded in to the FPGA, the FPGA can program the Boot Prom over SPI and can re-configure itself every time from the boot-prom. Can anybody give me pointers on how to go about this as my knowledge of JTAG is very limited.Thanks in advance.

 

Ananth

0 Kudos
6 Replies
Highlighted
Voyager
Voyager
12,776 Views
Registered: ‎08-30-2007

Re: FX2 Micrcontroller JTAG FPGA configuration

I have used an FX2 to program Xilinx parts several times in the past

and have been very pleased with the results.  One design used the 

Slave Parallel mode to load 8 bits at a time (very fast), another used

the JTAG port and FX2 firmware to bit-bang the data.

 

In both cases, we used custom firmware along with our custom FX2 driver.  It

was NOT a trivial task.  You can find a lot of pieces on the web, but I don't think

you'll find a complete solution.  There's lots of documentation on the web about

JTAG programming.  I believe Xilinx also has C code in one of their  app-notes

about processing XSVF files to extract the low level bit stream.

 

I hope this helps.

 

John Providenza

 

0 Kudos
Highlighted
Anonymous
Not applicable
12,764 Views

Re: FX2 Micrcontroller JTAG FPGA configuration

hi John,

 

thank you much for sharing your experience with me.  i am trying to reverse engineer a platform that has a FX2 whose port D pins(52,53,54,55 and 56) are connected to the JTAG port pins of the Spartan XC3S500E(PQ208). I am not sure if the FX2 uses the GPIF interface bus to bit bang JTAG. The custom firmware lets you stream the FPGA bitstream file directly. All other solutions that I have looked at use a SVF/XSVF player or a parser to decode the underlying bit pattern from a .XSVF file before streaming it to the FPGA. I thought this was interesting.In your implementations, did you parse a XSVF file or did you manage to stream the .BIT file to the FPGA directly?

 

regards,

Ananth

0 Kudos
Highlighted
Voyager
Voyager
12,725 Views
Registered: ‎08-30-2007

Re: FX2 Micrcontroller JTAG FPGA configuration

In one design, we used the GPIF and Bulk transfers with the Slave Parallel mode to load

8 bits at a time - very fast.

 

In another design, we used firmware to bit bang the JTAG i/f.

 

John Providenza

 

0 Kudos
Highlighted
Visitor
Visitor
9,861 Views
Registered: ‎08-13-2011

Re: FX2 Micrcontroller JTAG FPGA configuration

Sorry for replying to an ancient thread, but I thought I'd post a link to FPGALink[1] here because it may be of interest to others who stumble upon this thread.

 

FPGALink is an open-source cross-platform library that communicates with an FX2 chip over USB, allowing you to JTAG-program an FPGA, then read and write your FPGA design's registers/FIFOs at ~25MiB/s with an easy-to-use host-side API.

 

It supports many of the Digilent FPGA boards natively, but there's also an FX2 reference design[2] if you want to make your own PCB.

 

[1] http://www.makestuff.eu/wordpress/?page_id=1400

[2] http://www.makestuff.eu/wordpress/?page_id=446

 

0 Kudos
Anonymous
Not applicable
9,826 Views

Re: FX2 Micrcontroller JTAG FPGA configuration

Chris,

Thanks for the links to Your site. I became aware of Your work with the FX2-> FPGA when searching for relevant information. This gives me more inspiration to work on implementing cross platform host applciations based on FX2-> FPGA interfaces.

Thanks again!
Ananth

0 Kudos
Highlighted
Visitor
Visitor
9,509 Views
Registered: ‎11-19-2008

Re: FX2 Micrcontroller JTAG FPGA configuration

Hi Guys,

Does any one willing to share his experience of programing an FPGA with the FX2 using the GPIF.

I am also intrested in progamming a W25Q with the FX2.

Regards,

Yacine

0 Kudos