Chapter 5. F.A.Q.

For a list of known problems in current versions, please also check the "Bugs" tracker at the UrJTAG website!

Q. The documentation is incomplete. Where can I get more information?

A. Please ask in the "Using UrJTAG" Forum on

Q. My flash isn't detected or can't be programmed. What can I do?

A. Please record the output of the "detect" and "detectflash" commands and ask in the Forum. If possible, re-compile UrJTAG before with "—enable-jedec-exp" to get extra information.

Q. My CPU/FPGA/etc. chip isn't detected. What can I do?

A. First try to get hold of a "BSDL" description of the chip from the vendor, and specify where to find this file to UrJTAG using "bsdl path" before you "detect". Second, a bus driver has to be selected. Maybe "ejtag" or "prototype" work.

Q. When I type "cable parallel 0x378 DLC5" (in a Cygwin environment) I get "Unknown port driver: parallel"?

A. Please install the Cygwin ioperm package, and re-configure/compile.

Q. When I type "cable parallel 0x378 DLC5" (in a Cygwin environment) I get "Error: Cable initialization failed!".

A. Please install ioperm.sys driver using ioperm -i command.

Q. When running, I get "Can't exec "autopoint": No such file or directory"

A. You need the headers for gettext (e.g. Debian package "gettext-devel").

Q. When running, it complains about missing CVS

A. The easiest solution is to actually install CVS for this step, just to get around this error message.

Q. During compilation, I get "svf_bison.y: No such file or directory"

A. You need "bison".

Q. During compilation, I get "flex: can't open … src/svf/svf_flex.l"

A. You need "flex"

Q. During compilation, I get "src/svf/svf_flex.l", line 27: unrecognized %option: bison-locations"

A. You need a newer version of flex. It should be 2.5.31 or newer; Unfortunately, Cygwin comes with only 2.5.4a. You may try to compile and install a newer version of flex from source to solve this. The distributed source tarball contains source pregenerated with a current flex version, you need flex yourself only to compile from fresh SVN checkouts.

Q. When running "make install", I get "Permission denied" errors

A. If you want to install into a system directory (the default /usr/local is one), you'll have to run "make install" as the superuser, e.g. do "sudo make install".

Q. My BSDL file defines the bus DAT as bit_vector(15 downto 0), how should I access single elements?

A. BSDL syntax is an extension of the VHDL language. Array elements are indexed with parentheses: DAT(4) selects index number 4 of the DAT vector. Also refer to the "print signals" command.

Q. My board requires certain signals to be set to dedicated values before external memories can be accessed.

A. Most (if not all) BSR-based bus drivers allow for static configurations of pins that are controlled by BSR bits. Apply the required "set" commands before issueing the "initbus …" command. These settings are preserved by all bus related commands if they don't collide with the signals required for bus operation.

Q. My USB pod seems slow.

A. USB-based JTAG pods suffer from a couple of intrinsic issues. Consider the following to get maximum performance:

  • Run UrJTAG on native linux. Cygwin and VMWare are reportedly slower.

  • Connect the pod via a high speed USB hub to a high speed USB host port. Even though the pod is a full speed device, it benefits from the shorter turn-around times between host and hub.