USB Display/Touchscreen

Hello, Has anyone used a USB monitor interfaced to the "DisplayLink" chip on a Power PMAC? Monitors using this technology can be bought from companies such as Xenarc, Lilliput and Mimo. USB carries the video and touchscreen signals (I presume through an internal hub...). Most of the time these come with a generic HID touchscreen, so I'm more concerned if the video works with the Power PMAC. I was thinking of testing one but our CPUs are still on backorder. Thanks, KEJR

KEJR, We have used the one from MIMO and it works directly with the Power PMAC CPU through USB port and you don't need the video option for it however, you need the video firmware version which means you have to get the Power PMAC with 4GB memory option at least. The touch capability is a different issue though. As far as I know the guys at MIMO do not support Linux and we can't get the touch screen to work with Power PMAC since we don't have a Linux driver for it, but we may have better luck with other manufacturers.

We have ordered two Power CPUs with video option, so we should have the video firmware already according to your last post. What is the difference in the firmware? Do you have different kernel modules precompiled, or is it just the setup of the X server? Maybe we need the extra flash? Is there anything preventing us from editing our own image ourselves (We will be tailoring it for our own customizations of linux anyway)? I have read alot of postings on the (oddly enough) MP3Car forums regarding the lilliput displays and their touchscreens. I don't know if they use the same touchscreen chip as the MIMO or not, but there are alot of posts discussing how to get it to work. It seems that one of the problems is that the touchscreen reports coordinates in absolute, where other HID units (like a mouse) report incremental information. Some other issues I've read about pertain to the fact that some chips mask themselves as storage device IDs initially so that driver software can be loaded automatically on systems like windows. Its the typical complexity you expect for trying to make things simpler! I may get one of these units to test as we don't need (or have room for) a 15" display on all of our machines. I'll post back if I get it working with the touchscreen. Thank you, ~Ken (KEJR)

1.) There is no difference in firmware. Firmware, is a misnomer. We call the deltatau linux software package that we place in the /opt/ppmac folder, firmware. This package does not change whether you have video or not!!!!! 2.) We have a single embedded linux kernel that contains the drivers for the display link chip because that is what our video option uses. So the answer is no we do not have a different kernel modules. 3.) The reason we require a larger flash is because when we ship a unit with video we add the gnome windowing system to the filesystem and space gets tight. Shrinking the filesystem down to 1G with gnome would be difficult. A minimum of 4G is what I recommend when using video. 4.) You can get the touch screen drivers to work checkout the http://lists.freedesktop.org/mailman/listinfo/libdlo archive mailing list. I do recall making the MIMO video work a while back but I recall having to modify a kernel setting but cannot recall what it was. The setting to change came from reading the libdlo mailing list. 5.) Trying to compile your own kernel can lead to a headache we have an assortment of patches in it and version dependencies. If you need a kernel module don't embedded, just add it to the filesystem and use insmod. The linux kernel version we use is at. ftp://support.deltatau.com/DT-USA/Power%20PMAC%20Suite/Kernel/src [quote='KEJR' pid='467' dateline='1277212452'] We have ordered two Power CPUs with video option, so we should have the video firmware already according to your last post. What is the difference in the firmware? Do you have different kernel modules precompiled, or is it just the setup of the X server? Maybe we need the extra flash? Is there anything preventing us from editing our own image ourselves (We will be tailoring it for our own customizations of linux anyway)? I have read alot of postings on the (oddly enough) MP3Car forums regarding the lilliput displays and their touchscreens. I don't know if they use the same touchscreen chip as the MIMO or not, but there are alot of posts discussing how to get it to work. It seems that one of the problems is that the touchscreen reports coordinates in absolute, where other HID units (like a mouse) report incremental information. Some other issues I've read about pertain to the fact that some chips mask themselves as storage device IDs initially so that driver software can be loaded automatically on systems like windows. Its the typical complexity you expect for trying to make things simpler! I may get one of these units to test as we don't need (or have room for) a 15" display on all of our machines. I'll post back if I get it working with the touchscreen. Thank you, ~Ken (KEJR) [/quote]

Hello, Thank you for the detailed response. The extra space for gnome and related libraries makes alot of sense. It is somewhat becoming clear to me that we would be better off sticking with the Power PMAC "DisplayLink + 4GB flash" option so that we can minimize the dependencies on which display we use over the years on different machines. This is probably why you chose to develop this as an option as I can imagine supporting consumer grade devices with varying Displaylink chips to be a nightmare. The touchscreen appears to be a different beast, however. Elo and Microtouch don't seem to have a HDMI or DVI product in a display that is under 15" (their 12" is VGA DB15 only...). Most of our machines are small with meager display requirements so we have been forced to look at the "off brand" items such as the Lilliput. I've read alot of conflicting data regarding the lilliput touchscreens and chips (apparrently they use an egalax touch controller chip). Some people use the egalax HID driver built into kernel 2.6 and then just tweak their XF86 settings, while others say that you *need* to compile the kernel module from the manufacturer. Hopefully the lack of information means that the kernel driver works and people go with that. I guess we'll have to get a display and try it, at least they are cheap! Any advice on the touchscreen would be appreciated. Thank you, ~Ken