I have problematic modem connected to USB. I work on power consumption and I have to enable USB autosuspend after initialization of modem. If I do this after initialization there is problem, becuse autosuspend sometimes occurs after few times on/off display(after early suspend, because I use android), sometimes just after invoke usb_enable_autosuspend. I don't know why it doesn't work immediately. I am sure that modem don't send anything, so it should works. Maybe someone has this problem?
thanks for responses
Related
I am building IOT device using a LTE modem form Quectel, the BG95, together with NXP imx6, running Linux. The sim card I am using has the technology of eMTC.
Normally the device is working fine, the issue I am having now, is that the device lost LTE communication randomly (typically after 3-6 days uptime).
My setup
I have disabled echo mode in the BG95 at my init procedure.
I have a periodical call to send AT command "AT+CREG?" toward BG95, and read the response.
What I am seeing from the debugging is following:
My periodical at command "AT+CREG" toward BG95 is not responding.
Linux kernel reports ttyUSB towards BG95 is disconnected.
3-4 seconds, the kernel reports ttyUSB toward BG95 is connected again.
My periodical AT command "AT+CREG" toward BG95 is returning ERROR.
I see from the serial reading from the BG95 has "APP RDY".
I see from the serial reading from the BG95 has echo mode enabled.
Form what I am seeing, I am assuming that the BG95 is somehow "rebooted".
Is there any reason why the BG95 will reboot itself? Or how to confirm this?
I checked the datasheet of BG95, but I cannot find a AT command or other way to check the boot reason.
Do you have other suggestion on how to debug this further? Or similar experience with BG95?
Thanks
I manage a lab with computers running Win XP Pro SP3. For a lot of reasons it is important that the network cable is always plugged in. Unfortunately some guys like to unplug the network cable: in this scenario when network cable is unplugged a shutdown command starts as a punishment for having unplugged it. At the moment I accomplish this using a VBS script starting when user logs in that acts like an infinite loop like this:
Do
WMI code for checking network status...
Loop
But in this case script is alway running and uses a lot of cpu pertentage. Now, it is possible in VBS to write a script that is able to "listen" an event like the disconnection?
Please don't advice to change programming language.
Thanks in advance for any help.
You're using a lot of CPU because you're constantly checking the status while this is not actually necessary - just put a sleep in your loop and set it to like 10 seconds.
Either way this is a very bizarre way of approaching the problem - why not just talk with your workers instead? Maybe there's a legitimate reason why they're unplugging the network?
I'm interfacing to a hardware serial device using QT, I've based my application roughly around the Terminal example, but as the communication needs to be very synchronous the serial handler is living in another thread. The connection is via a 2xRS232 to USB adaptor with an FTDI chipset.
The serial comms are fine, I can connect, send commands, etc. However, when I quit and reload the application the serial port seems to be blocked.
Let COM1 be the connected device, COM2 is unconnected.
If I run the program, do a bit of talking to the hardware and quit, I can no longer connect to COM1 the next time I run the program (the data leds don't flash on the adaptor) unless I attempt to connect to COM2 first. Once I've tried this I can then connect back to COM1 as usual. This behaviour is not seen in the reference utility for the hardware and so must be down to some way I'm handling the port.
My close code is:
void mydevice::closeSerialPort()
{
this->stop();
serial->close();
emit serialClosed();
emit log("Serial port closed.");
}
serial is a QTSerialPort. First a stop command is sent to turn off the hardware (not relevant to the problem, it's just a convenience) and then I send a close command to the serial.
I have a subclassed QWidget for my main window, which calls this command on exit:
/* In the constructor */
connect(this, SIGNAL(WindowClosed()), mydevice, SLOT(closeSerialPort()));
void mainwindow::closeEvent(QCloseEvent *event)
{
emit WindowClosed();
event->accept();
}
Is there any reason for this behaviour? I assume I'm blocking the port open somehow, but surely it would complain that it's already open.
Another odd issue is that say the device is on COM1 and I open it in my application, COM1 is unresponsive in the other utility and the device appears on COM2. However, when I switch back to my program and fiddle a bit, the device appears on COM1 again (though always in COM2 in the other application).
So there seems to be a fairly simple solution, though I don't understand exactly what was causing the problem.
I have two threads, each controlling a different serial device. The serial configuration is accessed through a dialog which I stole from a QT example (the terminal). Each thread has an instance of this settings dialog. It seems that something goes wrong when selecting the port - for instance all the selections in the dialog actually point to the same COM port if checked in a debugger.
Anyway, I chalked this up to non-thread-safe code and changed the program to just ask for the serial port name as the data rates, stop bits, parity, etc are fixed by the hardware and aren't going to change. This has fixed the problem.
There are two possible answers, I think:
Your process doesn't terminate in spite of you closing the main window. How have you verified that the process is, in fact, terminated?
Your use of qt's serialport module exposes a bug in FTDI's driver. That's not unthinkable, but I'd call it a remote possibility at the moment.
Personally I don't see any use for the serial port emulation of the FTDI driver, it's adding an extra layer for no good reason. The D2XX interface is the way to do it, if you don't want to use something like libftdi. On Windows, I've found D2XX and libftdi to be the only viable alternatives, with libftdi working much better than D2XX on virtual machines.
Don't know if this could be useful.
I have a similar issue (but not the same) with a prolific pl2303.
In my case when i close the port (or even at startup, before opening it!), data is received anyway somehow and presented immediately when i open the port.
This happens only with an usb-rs232 adapter, if I use the ttyS0 (physical serial port) the problem does not appear.
The solution for me was forcing QSerialPort::clear() to clear buffers just after QSerialPort::open(). This avoids signal readyRead to be emitted and thus unwanted data to be received.
I'm rather unexperienced on the field of microcontrollers, I come from a Java background so the question might seem a bit noob but I didn't find much information on this.
So is it possible to debug an STM32F4 board via bluetooth (using eclipse or some othe IDE)? And if so could you send me some links that might help? We're building a robotic car controlled by a discovery board and debugging using an USB cable is not really an option if we don't want to disassemble the whole stuff every time something goes wrong. Hence this would really come in handy. So any help is appreciated
For doing this you would need to find a "Bluetooth Enabled" Debugger. I have never seen any and not sure whether there exists such thing or not.
I would suggest you one thing:
Assuming you have bluetooth connectivity between your board and your Machine,
Insert Debug strings: Send some strings from your board to your PC via Bluetooth. These strings will give you what's going on in Circuit.
For example, After Initialization, send "Init Completed" and like that. You can see these strings and see what's wrong.
I usually do this for my Wireless Device.
What you're wanting to do is really not practical; you're coming at this from way too high a level and trying to imagine the system as if it were running an operating system from the word go.
When you get the STM32 it as empty shell; you need to program it to do what you need to do and the only [sensible] way to get register-level debugging is to use a JTAG interface.
If, and this is a big if, you get it working reliably, but just want to give some debug information back while it is running, you could write a load of routines within the code to send out debugging messages when it enters certain parts of the program - and send it out over Bluetooth - but this is nothing like what you're used to single stepping through your Java code with Eclipse. If you want to do that kind of thing, you are going to have to put a little connector on that allows you to connect your JTAG or two-wire debugger cable to the processor. Even then, when you do that, you will be completely resetting your program and not simply single stepping through from where it went wrong.
You could insert a monitor program within your program to send out register values, program status etc over Bluetooth, but you still have to write the inital code and the only way to do this with out a ridiculous amount of trail and error is via your JTAG or two-wire interface.
Would this product work? It's a "IOGEAR Bluetooth Serial Adapter, GBC232A" for connecting to a serial port over bluetooth. I'm interested in wireless debugging too because my surface-clone dev computer only has one usb and this seems like it could be convenient over a tangle of usb cords and a usb hub. I have zero experience with any of this, so maybe you could validate or invalidate it as an option. I figure it just needs a proper serial connector wired up on the board and power from on-board?
I am trying to make U9 telit modem send SMS messages. I think I handle protocol correctly, at least, I manage to send them, but only under these circumstances: the native application was executed beforehand, and killed by task manager (without giving it a chance to initialize things).
It looks like the supplied application is good at doing certain initialization/deinitialization which is critical. I also see the difference between the two states in output of AT+CIND command. When I am trying to do things on my own, it returns zeroes (including signal quality), but when I run the same command after killing the native application, the output looks reasonable.
I am out nearly of ideas. I have tried many things, including attempts to spy at modem's COM ports (didn't work). Haven't tried setting windows hooks to see what the application is trying to get thru.
Perhaps you have encountered a similar situation?
Agg's "Advanced Serial Port Monitor" actually helped a lot. Sometimes it caused blue screen, but it helped uncover secret commands which seem to help. AT+PCFULL is not described anywhere on the net, for example. The real trigger of non-operatio was AT+CFUN, the power disable/standby feature.
Also, it appeared that we have more issues. At first, the modem appears on the bus only as disk drive. It doesn't want to appear as any other devices before the drivers are installed. So, the U9 Telit software sends an IOCTL to disk driver to tell the modem to reappear as more devices (modem, 3 serial ports, another disk drive).