Bitinfo is a simple utility that parses the header of a Xilinx bit file and outputs all the information that can be obtained from that header. This information includes the Xilinx FPGA the bit file was created for, the NCD file the bit file was created from, the creation date and time, and the bitstream length.
I had to reverse-engineer the file format to figure out how to parse all of this information. So that someone else doesn't have to repeat my work, I have included my reverse-engineering notes with the source code.
You may find this program useful if, like me, you often end up with several bit files lying around, all called "xc4005.bit," and you can't remember which one is the one you need. The header should at least give you some clues about the file's contents. Another use for this program is to prove to a student that the bit file they have brought to lab with them is not the one from this week's experiment, since the timestamp is from three weeks ago.
Update (10 Sept 2002): I received an email message from "Stephen from Australia" which corrected my understanding of the format of the header. The change should only affect FPGAs with large bitstreams (greater than 16.7 Mbytes). Steve's message didn't have a valid return address so I couldn't thank him. So Steve, if you are reading this page, thank you for correcting me. The new version of bitinfo is 0.2.
You can download the bitinfo source for free. It is released under the GNU Public License. See the GNU website for more details.
To compile bitinfo, first edit the Makefile if necessary. If you don't have gcc installed, you will need to change the first line from "CC=gcc" to "CC=cc" or whatever your C compiler is called. After editing the Makefile, type "make" and you're done. Although bitinfo was written for Unix, it has also been successfully compiled for Windows NT 4.0 using MS Visual C++.
To run bitinfo, just type "bitinfo < file.bit". You will probably want to put bitinfo in some bin directory for convenience.
Please report any bugs by emailing me at davesullins@earthlink.net.
Back to Dave's software page