I’m attempting to use an AV. io to capture the output of an Agilent MSO7104A scope. The output resolution should be 1024x768. A normal LCD monitor displays the output correctly. On the AV. io, the config tool reports the resolution as “1024x768p@60 RGB”, but it seems to have the pixel timing wrong and as a result the left and right edges are cut off. I can adjust the pan control to scan left and right, but I can’t get the full picture in the output. I have also tried selecting several different resolutions, but this just results in various combinations of black bars. It also looks like some of the vertical lines are “smudged”, which presumably is a result of sampling the pixels at the wrong time. Is there a way to adjust the pixel clock frequency through the configuration tool? If not, it seems like the auto-adjust routine in the firmware is broken and isn’t capable of figuring out what the proper timings are.
The config tool reports my unit as “AV. io HD Video (359577 4.0.0.40528) [2b77:3601]”, so it seems to be running the latest version of the firmware.
Hello Alex,
Thank you for reaching out on our forums, I’m sorry you’re running into further issues with your AVio HD! Unfortunately, it looks as though you’ve exhausted all the advanced options that the AVio HD offers for VGA signals. It is not possible to modify the pixel clock frequency of the AVio HD. The available advanced options can be found in the user guide here, https://www.epiphan.com/userguides/avio-hd/Content/VideoGrabber/UVC/4-Configure/VGAConfig.htm.
I’m afraid that this does appear to be a timings incompatibility, and that’s not something we can fix on the AVio HD. It’s possible that the DVI2USB 3.0 may have been able to compensate for this type of signal, as it has more possible configuration options. Though it has also been discontinued.
I’m sorry that we weren’t able to resolve your issue today, please let me know if you have any other questions, thanks!
Seems like it should be possible to set up the “focus” and “zoom” UVC controls to control the phase and frequency. Since it’s out of support, maybe I’ll try dropping the firmware in Ghidra and see if I can figure anything out. I thought you guys were doing some sort of canned VGA to HDMI conversion and that results in the lack of flexibility, but it looks like you have a VGA ADC chip (ISL98002), and both that and the HDMI receiver chip (ADV7611) feed into a Spartan 6 LX16 FPGA. Presumably the firmware running on the ARM core in the CYUSB3014 handles the configuration; seems like it shouldn’t be all that difficult to get better control over the Htotal and phase settings on the ISL98002. Seems like there might not be a good way of supporting oddball resolutions, but perhaps the firmware can simply be edited to add nonstandard resolutions.
I’m also not super happy with the colors in the captured video. While it does handle the 640x480 output of my 8753E reasonably well (it’s only wide by 3 pixels or so, and there are obvious vertical bands where those pixels get skipped over), the color is terrible presumably due to the subsampling. The 1 pixel wide trace isn’t consistently yellow, it is splotches of yellow and white. Adding a custom resolution of 1280x960 does help with the color, but it still gets cut off on one side or the other.