USB CDC-ACM on STM32 device not registering on Linux - usb

Working with the STM32L062 Cortex-M0 and CubeMX the generated USB CDC-ACM code works fine in Windows. With loopback code running on the STM32 and TerraTerm running on Windows characters typed in the terminal window correctly echo back. However, when this same system is then plugged into a laptop running Ubuntu, the device fails to enumerate. Even worse, the system doesn't appear to respond to the connection whatsoever- no new messages appear via dmesg that even a failed enumeration is going on. Given that the code used is generated by CubeMX wizards it is difficult to know what to start to troubleshoot. Any suggestions?
As an aside, this isn't the first issue presented by CDC-ACM drivers. Implementing a USB CDC-ACM stack for a PIC32MM processor, data can be sent to the host but not received from the host, however, if the driver is switched to plain vanilla CDC then data can be sent both ways no problem. So it seems maybe Ubuntu has some issues with the default USB drivers, but either way, it's very odd that the ST driver gets zero response at all from the system.

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STM32F04 in DFU mode recognized only when powered from battery (Win10)

I made a STM32F042k6, battery powered device, that I would to flash vi DFU protocol.
In order to do so I disconnect the battery, I pull BOOT0 to VCC, and then plug the device in USB3 port of PC (no USB2 available). The device is not recognized and showed
VID:0000 PID:0002 (case I)
However, when I first connect battery, and then connect the device to PC it is recognized without a fuss (case II).
The problem I face is that I would like to initiate jump to bootloader program by command in software - but then I reach exactly the same condition as in case I.
Could you help me to identify what conditions for proper boot I am violating?
EDIT:
The way I have discovered the problem was when I implemented software jump to bootloader. It seemed not to work at all (VCP device dissapeared, and erroreous <> device appeard in system PID:0002 VID:0000).
I wanted to enter bootloader by pulling up BOOT0 pin, but I could see that I sucseed only when battery-power cycled. USB power cyccle resulted in the same "failed descriptor" device.
I suspect that when powered on via USB, the booloader has som ecommunication problems and cannot establish proper PID and VID. When powered via battery - this problem is not existing.
Do you have a discovery board?
I read in the STM32F042x4/x6 Reference Manual (DocID025832 Rev 5):
The STM32F042x4/x6 embeds a full-speed USB device peripheral compliant
with the USB specification version 2.0.
(part 3.19, p.27).
In the AN2606 (Rev 33), a table shows the USB configuration which is used by the DFU Bottolader in USB FS (Full-speed):
I assume that the USB in the bootloader is the 2.0, but USB 3.0 must be USB 2.0 compliant. So it is possible to use an USB 3.0 port.
I suggest you use the DfUSe Demo from ST. Its interface consists of a tab where the DFU devices available are displayed when detected. I try it on another STM32x by following these steps:
Open DfuSe Demo software.
Plug BOOT0 to Vdd to put the micro on DFU mode.
Plug the USER USB to your computer port.
The name of your device should appear in “Available DFU Devices” field.
You could try to use directly PA11 and PA12 as well (according to Table 12) instead of the USB port of your board.
EDIT:
Another solution to upgrade your firmware without driving boot0 is to jump directly into the DFU bootloader of ST inside your firmware. Else you could design your own IAP bootloader (In-Application Programming).
I hope that helps.
I faced this same issue with the STM32 Mini F401 and dug into it for several days. Unlike the OP I was unable to find any electrical conditions which reliably got the bootloader to do the right thing. I was able to program my board maybe once every 20 tries, which was really slowing down my process.
In the end I discovered that I can go to the Windows device manager, show hidden devices, and there will be an entry in Universal Serial Bus Devices called STM32 BOOTLOADER. When the issue is happening the board is connected in dfu mode but that device is not marked active in the device manager.
To resolve the issue consistently, you can manually delete the hidden STM32 BOOTLOADER entry, uninstalling the device (no need to delete the driver, just uninstall the device). Then reboot your board in DFU mode and it should connect as expected every time. Unfortunately I need to do this process every time I want to program, but that's far better than the inconsistent/intermittent failures before.

How to reverse-engineer a USB device without monitoring traffic?

How is it possible to determine the commands to operate a usb device, if that device comes from another operating system and traffic monitoring software cannot be installed on that OS. The only method i can think of is sending random commands to the device, until the device responds, but this seems implausible for more complex commands, and potentially dangerous. For example, consider the DualShock 4 controller. Sony has not made an official driver for this device, so what method can i use to create a linux driver for it?
Get a hardware protocol analyzer. Then you won't need to install any software on the host or device under test. Here is one that I have used:
http://www.totalphase.com/products/beagle-usb12/

USB device detection problems: using Compact Flash card reader and QNX (Virtual Machine)

First of all, there's a similar thread on OpenQNX posted years ago but the solutions don't really apply for me.
Having said that, I want to create an OS image of QNX 6.6.0 to put on a Compact Flash card. This card is plugged in an USB adapter which is connected to my host pc. I'm running Neutrino in a VM (VMware/VirtualBox) for which I enabled USB support. Generally, the adapter works fine under Win (current host) and Linux.
The (apparently out-dated) tutorial I was following stated to search for devices named umass* or hd* after connecting the USB adapter. But there aren't any (except for hd0).
See also "ls /dev" screenshot.
The processes devb-umass and io-usb are running. So I expect that the adapter is detected automatically.
Any suggestions what went wrong?
OK, it seems that I had to restart the usb driver 'devb-umass' (several times). When the card reader is already plugged-in during the booting the driver will not detect it autoamtically. Thus one has to unplug and plug it in again after the devb-umass was getting re-started. It also might have been that the Host Controller Driver (HCD) was set to 'ohci' instead of 'ehci'.
Everything is working now as expected.
(Thanks Tim from the OpenQNX forum! ;) )

Virtual COM Communications Issue

I'm working on a Communications Device Class (CDC) driver for an embedded device, a Full Speed implementation of USB 2.0. The COM port settings are 115200, 8-bit, no parity, 1 stop bit, no flow control. Our PC application (32-bit, Windows 7, .NET 2.0) communicates with the target device through a virtual COM port, which on the target device can connect to either a FTDI (USB-to-SCI bridge) chip or the integrated USB peripheral in the microcontroller, depending on which port is selected by the application.
Both virtual COM ports work without any problems using Realterm. However, while our desktop application works using the virtual COM port connected via the FTDI chip, it hangs when attempting to use the virtual COM connected via the microcontroller's integrated USB peripheral.
When connected via the virtual COM port using the integrated USB, the application consistently hangs on the second call to SerialPort.Write(...). Using Serial Monitor from HHD Software I can see that the data is transmitted on the first call to SerialPort.Write(...). However, that data is never received by the target device.
It's odd because the only time I have seen similar problems on previous projects was when the flow control settings on each side of the bus were mismatched.
Additional info...
Here is the data captured from various port monitoring tools while running our PC application connected to the target device via its integrated USB peripheral. Any insight would be appreciated.
Sysinternals Portmon
Advanced USB Port Monitor
Device Monitoring Studio - Request View
Device Monitoring Studio - Packet View
For those that are interested, I am using CodeWarrior 10.2 with the MCF51JM128 from Freescale.
Any ideas or suggestions would be appreciated. Thanks.
It is clear from the logs that you are making the classic mistake of not taking care of the hardware handshaking signals. That only ever works by accident, a terminal emulator like Realterm will never make that mistake.
You must set the DtrEnable property to true. That turns on the Data Terminal Ready signal. It is important because RS-232 is an unterminated bus so is subject to electrical noise when the cable is disconnected or the power turned off. DTR convinces the device that it is in fact connected to a powered device. This is emulated of course in your case but the driver or firmware will still typically implement the RS-232 behavior.
And the RtsEnable property is important, used to handshake with the device and prevent the receive buffer from overflowing when the app isn't emptying the buffer in a timely matter. You really should set the Handshake property to Handshake.RequestToSend, the most common way a device implements it. Which then also takes care of turning RTS on. If you have to use Handshake.None for some reason then you have to turn it on yourself by setting RtsEnable to true.
This ought to take of the problem. If you still have trouble then use PortMon to spy on the way Realterm initializes the driver. Compare the commands you see against the commands that the SerialPort class sends. Make sure they are the same. In value, not in sequence.

USB HOST mode in ICS

I'm trying to connect a usb sensor (see Toradex) to an android phone (Desire Z) running android 4.0.3.
To test this, I wrote a small app to enumerate the attached device(s).
This supposed to have USB HOST mode implemented and to power the usb sensor (HID)... but it doesn't.
I got a USB OTG cable and now, when I attach the cable, a small icon appears in the status bar (car mode).
I'm disappointed since I waited for this feature for awhile now...
Any thoughts? I read almost everything out there related to this (Sven work and whatnot) but I might have missed something...
Thanks!
I have worked a lot in the past year and a half to build custom android platform. Some was under Froyo but mostly on Gingerbread. Most on the hardware I added was on either a UART or on USB, which is what you want to do. Unfortunately, it is not as easy to add a USB peripheral on an Android device than on a PC or a MAC. PCs and MACs have virtually unlimited memory space (hard drive). They can hold the drivers of a very large number of devices. That makes it possible to do auto-detection and automatic loading of drivers. On an Android device, it is a lot more lean therefor, just the required drivers are stored on the device. Every time I added a new device, I had to compile the driver for my platform and make some modification in my configuration. It is also possible to load the driver as a module instead of compiling it with the kernel (gives a file.ko output). Although, the driver must have been written accordingly. But, you will have to install it by modifying the "init.rc" which requires root privilege.
here is a few link of question/answer about about drivers in Android. That should give you a little bit more info:
USB touchscreen driver
Hope it helps but unfortunately, it is quiet a lot of work do do.