I am running a flow graph on multiple E310s using network mode and one of them keeps printing "L" to the screen then stopping. I have searched the internet and found this link: http://files.ettus.com/manual/page_general.html#general_ounotes, but it only explains the overflow/underflow, not what the "L" means. Thanks for the help!
First of all, the network mode was never meant for productive usage – it's primarily a diagnostics tool for manufacturing, and has already disappeared from the development version of UHD, and will probably disappear from the next SD card image release for the E310.
"L" stands for late. This means that you've sent samples to the E310 that have a time spec supplied in the tx_metadata, but that time has already passed when the samples reach the device.
Related
I was able to make a working HID USB stack on my "StartUSB for PIC" board for the 18F2550 microcontroller. I based it on one of the MLA libraries, which was made for the 18F45K50 (MLA 2018_11_26, hid_custom, picdem_fs_usb_k50.x), but I converted it to work with the 18F2550 (there might have been easier ways, but only learned to work with PIC about 1 month ago). On the host side, I'm using LibUsbDotNet (also here, there might be easier ways - the documentation on this library really sucks) on a Windows 10 machine.
I'm using the HID class, full speed, and all seems to work. Although, I get some random errors on the host PC (see below), but doing one close/re-open cycle on the host side when getting the error is kind of solving it. Dirty, but it works. So I kind of ignore this now.
Win32Error:Win32Error:GetOverlappedResult Ep 0x01
995:The I/O operation has been aborted because of either a thread exit or an application request.
I'm not an expert on USB (yet). But all examples I'm seeing are based on 1) you send first a command to the device and 2) then you retrieve the answer from the device. I did some performance tests, and see that this indeed shows that I can do about 500 cycles/second. I think that is correct, because each cycle, sending command and retrieving answer, each takes 1 msec.
But do I really need to send a command? Can't I just keep reading endlessly, and when the device has somthing to say, it does send the data in an IN transaction, and when not it ignores which creates a timeout on the host side. That would mean that I can poll at 1000 cycles/second? Unfortunately, I have tried it by changing my implementation on the PIC, but I get very weird results. I think I have issues with suspend mode. That brings me to another question - how can I make the device get out of suspend mode (means that not the host, but the device should be triggering this event). I have searched the MLA library for command such as "wakeup", "resume", ... but couldn't find anything.
So, to summarize, 2 questions:
Conceptual: Can I send data from device to host without being requested for it by a command from the host?
For PIC experts: How can I have a device trigger for a wakeup from suspend mode?
And indeed, the answer is Yes on the first question.
In the meantime, I found another link on the web that contains a Visual Studio C# implementation of a USB library including all the source files.
If you're interested, this is the link
This C# host implementation works as a charm. Without sending a command to the device, I get notified immediately if a button is pressed. Great!
It also proofs that my earlier device implementation based on the original MicroChip MLA, is 100% correct. I stress tested the implementation by sending a "toggle LED command" as fast as I could, and I reach 1000 commands/second. Again great!
I think that LibUsbDotNet isn't that perfect after all. As I wrote above, I get rather unstable communication (Win32Error). But with this implementation, I don't get a single error, even after running for half an hour # 1000 commands/second.
So for me, case closed.
Hey so what I'm trying to do is take HDMI input (from a computer) to a splitter from which one channel goes to some viewing device (projector or something) while the other channel goes through a capture card into another system for some processing that I'm doing. However, four seconds after I connect my capture card to one of the splitter's output channels the splitter just stops outputting on that channel and essentially shuts that channel off (as seen by the LED on it). However, if I connect a projector to the other output channel it stays working fine on that.
Keep in mind that the input I'm using is from a MacBook Pro. When I switch the input to an Xbox 360 everything works absolutely fine. Also, if I connect the input (MacBook) directly to the system bypassing the splitter it works absolutely fine. Can someone explain what might be going wrong here when I put the splitter in the mix?
Here is the equipment that I'm using:
Splitter: http://www.gofanco.com/2-port-hdmi-splitter-4k-black-splitter2p.html
Capture Card: https://www.amazon.com/Video-Capture-Device-1080P-Grabber/dp/B01N4SM7H6/ref=sr_1_7?ie=UTF8&qid=1522955789&sr=8-7&keywords=full+hd+video+capture
Any help would be greatly appreciated :)
I would guess this may be an EDID issue. A display or capture device negotiates the best resolution and frame rate via EDID with your graphics card.
Now if you put the splitter in between the EDID based communication can go sideways.
HDCP could be another reason. Your splitter may not correctly handle or advertise HDCP
We’ve been using the Tokbox platform for several months now with a Javascript web-client as well as an Android phone client, where sessions and connections are managed by a Python server. While integration and bring-up went well on both ends (client and server), we continue to encounter problems with the in-session audio and video experience.
Sessions are always routed and always between two participants only, with much use of a collaborative editor.
The in-session experience is like a coin toss: we never know how it’s going to go, and that’s becoming a business threat.
Web-Client: A/V Resources
The most common problem is the acquisition of audio and/or video: at the beginning of a session, one or the other participants may have problems hearing or seeing the other. Allocating a new connection to establish new streams does not fix that, nor does restarting the browser.
Question: What’s the recommended way to detect possible resource locks (e.g. does another application hog the camera/microphone)?
Web-Client: Network
Bandwidth and packet loss are a challenge, for example this inspector graph:
Audio and video of both participants is all over the place, and while we can not control the network connections the web-client should be able to reliably give useful information.
Question: Other than continuous connection monitoring with getStats() and maybe the experimental navigator.connection property, how can the web-client monitor network connectivity?
Pre-Call Test
We recommend to customers to run a pre-call test and have implemented it on our site as well. However, results of that test often times do not reflect the in-session connectivity. Worse, a pre-call test may detect a low (no video) bandwidth while Skype works just fine.
Question: How can that be?
I'm a member of the TokBox development team. I remember you reported an issue with the Python SDK, thanks for that!
Web-Client: A/V Resources
Most acquisition issues are detected by the JS SDK and if they aren't then we'd really like to hear about it! Please report reproduction steps or affected session IDs to TokBox support (referencing this StackOverflow question): https://support.tokbox.com/hc/en-us/requests/new
Most acquisition errors appear as OT_HARDWARE_UNAVAILABLE or OT_MEDIA_ERR_ABORTED errors. Are you detecting and surfacing these errors to your users? There is also the special OT_CHROME_MICROPHONE_ACQUISITION_ERROR error which is due to a known issue with Chrome that has been mostly fixed since Chrome 63 (see https://bugs.chromium.org/p/webrtc/issues/detail?id=4799).
Web-Client: Network
Unfortunately this is one of the more difficult issues to troubleshoot. Yes, Subscriber#getStats() is the best tool we have at our disposal and is a wrapper around the native RTCPeerConnection#getStats() function. Unfortunately we don't have much control over the values returned by the native function and if you think our SDK is returning incorrect values when compared with values from RTCPeerConnection#getStats() then please let us know!
It would be worthwhile confirming whether the issue is reproducible in all browsers or only a particular one. If you have detailed data regarding the inaccuracy of the native RTCPeerConnection#getStats() function then we could work together to report it to the browser vendor(s).
Fortunately we have just released the new Publisher#getStats() function which lets you get the publisher side of the stats. This should help you narrow down the cause of a connectivity issue to either a publisher or subscriber side. Please let us know if this helps with tracking down these issues.
Pre-Call Test
Again, these tests are based on Subscriber#getStats() which in turn are based on RTCPeerConnection#getStats(), the accuracy of which is out of our hands, but we'd love any reproduction steps to either fix a bug in our client SDK or report a bug to the browser vendors.
Just to confirm though, when you say you've implemented a pre-call test in your site, did you use the official JavaScript network test module? https://github.com/opentok/opentok-network-test-js This is actually what's used by the TokBox pre-call test.
#Aiham, thanks for responding, I've been looking at the the new Publisher#getStats() you linked to (thank you!), so we too can give our users some way of visibly seeing the network conditions that might be affected the quality of their call (and who's causing it). However, it seems as though bytes / packets sent goes up sharply as the number of subscribers increases, even though we're in a routed session.
Am I wrong to expect the Publisher#getStats() statistics to stay fairly stable regardless of the number of subscribers then receiving that stream in a routed session? I expected the nature of a routed call to mean it's sent once to the OpenTok Media Servers, and the statistics would end there.
In my current scenario, I'm using NETLIGHT Pin (Pin no. 64) of SIM800 module with my PIC microcontroller to know whether my module is registered or not?
This way I built the circuit. Just I removed LED from VBAT. Then I connect collected of NPN transistor to pic micro input PIN.
I want to know whether any easy way using AT commands to find network registration status of SIM800?
Unfortunalty it's seem not to be really possible (or in fact detecting this state in only one way)
I use SIM800 and let it run for hours and I have seen many cases of network loose, while the AT+CREG? continue telling everything is OK.
Also, even with network down, the SIM800 continue sending you the name of the operator and the strengh of the signal.
The only way I've found is to monitor the serial port: when the SIM800 loose the network, it sends two messages:
+PDP: DEACT and
+SAPBR 1: DEACT
I suggest you to have a look at the document "SIM800 Series_AT Command Manual" and especially the chapter "19.3 Summary of Unsolicited Result Codes". You'll find +PDP and other interesting code (like under-voltage warning, DNS failed...) and see some of these messages are not linked to AT command.
From the manufacturer's documentation:
We have developed an application on Windows.net mobile framework and it is used on a Windows 6.5 Smartphone. for our location based application. Our application is real time and tracks our employees. We are finding that the device loses its GPS signal.
Has anyone managed to restart the GPS receiver so that it starts giving the GPS signal again. I would be ever so gratefull if someone can help. We are using GeoFramework2.0 to deliver the geographic information that you need.
Regards
Sandy
The GPS is "shut down" when no application is using it. Just close your handles and re-open them.
If the GPS on your device is part of the WWAN radio (i.e. cellular phone) it may get put in to a low power state rather than being actually shut off. In that case, you can try restarting the radio.
If that doesn't work, some GPS's will allow you to send proprietary commands to them to force a reset or clear the memory. These commands are not standard and will differ significantly by manufacturer. If you have a SiRF GPS, take a look at the SiRF Binary Protocol Reference.