Change PicoBlaze ROM Code on Spartan 3E Development Board

Hello everybody,

do You know how to change the program of an existing PicoBlaze 
implementation on a Xilinx Spartan 3E development board? The board uses 
an USB cable to download the bitstream to the FPGA.

I have an existing design including a PicoBlaze processor and would like 
to change its ROM code without recompiling the complete project. The 
JTAG loader software only seems to work with the parallel port cable, at 
least it tells me so.

Thanks for Your advice,

Markus Fras

Markus Fras wrote:
> Hello everybody,
> 
> do You know how to change the program of an existing PicoBlaze 
> implementation on a Xilinx Spartan 3E development board? The board uses 
> an USB cable to download the bitstream to the FPGA.
> 
> I have an existing design including a PicoBlaze processor and would like 
> to change its ROM code without recompiling the complete project. The 
> JTAG loader software only seems to work with the parallel port cable, at 
> least it tells me so.
> 
> Thanks for Your advice,
> 
> Markus Fras

Read your Spartan-3E Development Board User Manual.

It explicitly covers reconfiguring the PicoBlaze code *without* 
performing another place & route, though that's an option as well.

The tools are available from the Spartan-3E development board web page 
(or perhaps with the PicoBlaze suite) to give you the reprogramming 
capability for a live board.

All the info you need is there.