HP 8920 screen grabber
| Repository: | http://gitorious.org/hp8920-screen-grabber |
| Mailing list: | http://groups.google.com/group/qt-ham |
I wrote a little tool, the HP8920 Screen Grabber to make screen shots from the nice RF test set HP8920A.
The HP8920 can create screen dumps in at least two methods:
- using the (expensive, but fast) GP-IB. This bus is also know as HP-IB or IEEE-488 or IEC-625 and even a bunch of even lesser known names.
- using the (cheap, but slow) RS232 serial port
As I lack GP-IB hardware, I'm using the second method.
Preparations
In the manual, and also at http://www.amtronix.com/8920btsinfo.htm you'll find the connection of the RF11 socket at the rear. So we need a connection cable.
Please note: it's a 6-pin RJ-11 port, not an RJ-45 socket. But that didn't really matter. I just needed one of the serial ports. And by luck this was Port 9, which is on the 4 inner pins. So I was able to re-use an old RJ-45 telephone cable from my scrap box. I also readily had a SUB-D plug with 9 pins. And now for some happy soldering.
Configuration
Configure the HP8920A like this:
BTW: this screen shot has been made with my program.
Download & compilation
Download the source from my Git repository.
Assuming that you've got Qt 4.x already installed, you should now only do:
$ qmake-qt4
$ make
$ ./8920grabber
No, not really, because I currently did hard-code my serial port into the program. If you don't use /dev/ttyUSB0, then please modify mainwindow.cpp near line 61.
Operation
The rest is pretty simply. Press SHIFT and PRINT on your HP8920 and you'll see the image trickle in. This old device can't do more than 19200 baud. And it doesn't use any compression in it's PCL, so the transfer takes some seconds. You'll see intermediate updates to keep you in a healthy, unbored state, thought :-)
