I have Raspberry Pi 3 plate with connected USB to UART (COM) converter.
The power led on the USB stick is ON.
I can not find the converter in Windows Device Portal.
In both: connected and disconnected states I see just two UART related records in Device Manager:
(ID:ACPI\BCM2835\0, Class:System, Manufacturer:Microsoft, StatusCode:25165834)
>BCM283x Mini UART Serial Device
(ID:ACPI\BCM2836\0, Class:Ports, Manufacturer:Microsoft, StatusCode:25182218)
>ARM PL011 UART Device Driver
(ID:ACPI\BCM2837\4, Class:System, Manufacturer:Microsoft, StatusCode:25165834)
Also I use git diff between saved device lists and there is no difference between the case I connect USB stick and disconnect it.
Where can I see the device in the list?
UPDATE
Here I print all found devices:
First you need make sure your USB to UART (COM) converter is supported on Windows IoT Core. Please check the hardware compatibility list. The CP2102 USB 2.0 to TTL Module Serial Converter is supported.
I use CP2102 USB to UART Bridge Converter and it also works. Use the SerialUART sample can list two device: one is on-board PL011 UART Device and the other is mine.
From device portal:
Related
I made a custom USB sensor device that runs on a Windows 8.1 / 10 desktop computer using the WinUSB driver (I implemented Microsoft extended USB descriptors in device firmware to automatically install the driver when the device connected).
Can I use a WinUSB device on HoloLens2? Or, if there is no WinUSB support on HoloLens2, how can I use my USB device with a “custom USB device class”?
At the moment, I do not have a hololens2, but I need to understand how the USB works on it.
Edit: I found this link: https://learn.microsoft.com/en-us/hololens/hololens-connect-devices#hololens-2-connect-usb-c-devices
It says that hololens2 supports the following device classes:
Mass storage devices (such as thumb drives)
Ethernet adapters (including ethernet plus charging)
USB-C-to-3.5mm digital audio adapters
USB-C digital audio headsets (including headset adapters plus charging)
Wired mouse
Wired keyboard
Combination PD hubs (USB A plus PD charging)
My device does not implement any of these classes (custom class). Is there a chance to make it work on hololens2?
I finally tested my code and USB device on real Hololens 2. The USB device works great there because Hololens2 supports WinUSB! The WinUSB driver was installed automatically (my device has WinUSB descriptors).
According to the documentation you referred, all classes HoloLens2 supports have been listed, and unlisted classes are not supported.
Could you provide more information about your business request and submit a feature request via feedback hub on new feature request to be considered in future releases of HoloLens OS and devices?
If it’s a hot impacted feature, it will be possible to be given priority to jump in the development schedule. Actually, the existing classed on HoloLens 2 are also based on user’s feedback in such way.
For how to post feedback request, you can follow this doc: Send feedback to Microsoft with the Feedback Hub app.
I am working on a project which has a Raspberry Pi 3 Compute Module integrated into a hardware design where the PCB provides access to both Serial Ports on the compute module:
One serial port with TX/RX on GPIO 14/15 (pins 51/53 of module)
One serial port with CTS/RTS/TX/RX on GPIO 31/31/32/33 (pins 34/36/46/48 of the module)
As far as I understand there is one full 16650 compatible UART available in the BCM2835 called the "PL011", and one mini-UART which is normally used to communicate with the internal BlueTooth chip.
When booting Raspbian Jesse, I see the /dev/ttyAMA0 device which seems to communicate on GPIO pins 14/15, and according to what I have read this communication runs through the PL011 full UART chip. I have tried to create a /boot/config.txt file which has the following device tree overlays:
dtoverlay=uart1,txd1_pin=32,rxd1_pin=33
enable_uart=1
This does not seem to provide me with a /dev/ttyAMA1 device. This seems consistent with the description in the /boot/overlays/README file which states:
Name: Uart1
Info: Enable uart1 in place of uart0
I did find a limited driver for the mini-UART which is fixed at 115200 baud, which seems like a driver to use the mini-UART instead of the full UART.
What I'd like to do is: without redesigning the hardware, configure the "PL011" full UART to use the CTS/RTS/TX/RX port, and the mini-UART to use the TX/RX port, so that I can use both serial ports in my application.
Hopefully I will have more luck today. I have no prior USB integration and about 8 months of learning embedded systems on Atmel devices. I am trying to use an Atmel SAM L series to connect over USB to a computer. The use case is for data transfer. Specifically, the MCU will be gathering data from it's sensors and packaging it for USB transfer.
I have searched through and read up on all of Atmel's included USB examples. I have also started reading through usb.org's class specifications for CDC.
I have running now something that lets me send data along one com port, into the target usb and then out the debugger usb to another com port. However, I don't think this is real USB.
My problem is two fold.
1.) I do not fully understand what differentiates USB from serial communication on a com port.
2.) Even if I were doing it correctly, I'm not sure how to test and verify that I have indeed created a legitimate USB device that can be accepted by a host computer.
Links to documentation(Atmel or generic) or example code would be appreciated.
1) USB is defined in the USB specifications from http://www.usb.org. Serial ports were an older and simpler interface that involved sending data back and forth asynchonously on pins with names like TX and RX. The USB CDC class and its ACM subclass allow you to make a USB device that emulates a serial port. If you make your device be a USB CDC ACM device, then you don't need to supply any drivers for Windows 10, Linux, or Mac OS X.
2) You can read the USB specification and the CDC ACM specification. You can run the USB command verifier. You can test your device with a variety of different USB hosts to make sure it works.
I'm trying to implement UART over a USB interface on the STM324x9I-EVAL development board. The purpose is to send commands to a servo controller (or other hardware, for that matter) serially. I've successfully implemented the USB_Device_CDC example on the development board but am unsure exactly how this works without a PC with drivers on the other end. As far as other hardware is concerned, will the USB port now simply look like a serial port? Or is there still a need for a driver or some sort of interface on the other end?
I do want to point out that I'm aware of the following post:
Emulating UART over USB
but I don't believe my question is fully answered within the context of that answer.
A USB connection is not a peer-to-peer connection like a UART. It requires a host and a device in a master/slave relationship. The device cannot initiate data transfer; it must be continuously polled by the by the host.
A CDC/ACM class device presents a virtual COM port on a PC host, but that does not allow the device to communicate with a UART interface. It looks like a serial port at the software level, but does not implement a UART physical layer. There is an awful lot going on under the hood to make it look like a PC serial port, but none of it resembles UART communications at the physical level.
There are devices that act as UART/USB bridges (from FTDI and Prolific for example), and you could (somewhat expensively) build your own from a microcontroller that has a USB device controller and a UART, but the bridge is a USB device and must still connect to a USB host; these are normally used to connect a PC to a microcontroller that lacks a USB controller or where the software/CPU overhead of using a USB controller is too great.
In theory you could connect a microcontroller that has a USB host controller to one that has a USB device controller, but you need host and device software stacks on each respectively, and once you have the USB connection, implementing CDC/ACM is a somewhat inefficient use of the available bandwidth. The purpose of the CDC/ACM class is primarily to allow "legacy" software to work on a PC.
If you need to connect to a "real" serial port, you should use a real UART - which are far more ubiquitous than USB controllers on microcontrollers in any case.
You should learn a little bit about USB device classes. CDC is a USB device class, and ACM is a subclass that I assume you are using. The device you made could be called a "CDC ACM device" because it uses the CDC class and the ACM subclass.
These classes and subclasses are defined by the USB Implementers Forum in documents that you can find here:
http://www.usb.org/developers/docs/devclass_docs/
These documents specify things like what USB descriptors a CDC ACM device should have in order to describe itself to the host, and what kinds of interfaces and endpoints it should have, and how serial data will be represented in terms of USB transactions and transfers.
Note that CDC ACM only specifies some USB commands for transferring data between the host and the device. It does not specify what the device will actually do with that data. You can use CDC ACM to implement a USB-to-serial adapter, or you can just use it as a general purpose communication interface for whatever data you want to send.
Yes, you do need a driver on the PC side. The driver needs to be designed to run on your specific operating system. It needs to create some kind of virtual serial port device in your operating system that other software (which only knows about serial ports) can find and connect to. It needs to translate serial port operations performed by other software on the serial port (e.g. writing some bytes to the serial port) into low-level USB commands according to the CDC ACM specifications (e.g. sending some bytes out to the device on a particular endpoint in the form of USB packets). It needs to somehow know which USB devices it should operate on, since not every USB device is a CDC ACM device.
For Windows, you will probably use the usbser.sys driver which comes with Windows. For versions of Windows older than Windows 10, you will need to write an INF file to associate your device to usbser.sys and sign it. For Windows 10 and later, there is a new INF file called usbser.inf already included with Windows which will automatically match any valid CDC ACM device. This means you don't have to write or distribute a driver for CDC ACM devices if you only intend to support using the device on Windows 10 or later. The partnership between Microsoft and Arduino which began in 2015 gives me hope that Microsoft will continue supporting and improving usbser.sys in the future. In fact, they claim that in Windows 10 "the driver has been rewritten by using the Kernel-Mode Driver Framework that improves the overall stability of the driver", so that is good news.
For Linux, there is the cdc_acm kernel module, which has been a standard part of the kernel for a long time and should work automatically with any CDC ACM device you plug in.
For Mac OS X, there is the AppleUSBCDCACM driver, which should work automatically with any CDC ACM device you plug in.
Note that for any of these drivers to recognize your device and work with it, your device has to have certain values in its USB descriptors, and the requirements can vary depending on what exact driver version you are talking about.
Will the USB port now simply look like a serial port?
No, that's the wrong way to think about it. The USB port will still look like a USB port, but the various USB drivers provided by your operating system will recognize that a CDC ACM device is plugged into that port and create a new entry in your operating system's list of serial ports. Then if you run some software that only knows about serial ports, it can connect to that port.
In fact, if you make a composite device, you can have a single USB device plugged into a single USB port that actually has two or more virtual serial ports.
I want to connect a USB peripherals to a FPGA. Basically FPGA should act like an USB host. Is there a FPGA board support a USB hub so that one could connect multiple(upto 4) USB peripherals at a time.
I have a Digilent Nexys3 fpga which is based on Spartan 6. It supports only one USB device (keyboard or mouse). It doesn't support a hub. I have found Cypress host controllers, but I am not sure how to use it in a FPGA.
You need to have a USB host controller inside your FPGA, such IP is not freely available, one alternative is to use a Zynq based (for Xilinx) or Cyclone V based (for Altera) board. Those have integrated USB controllers connected to their dual ARM core.
You can find more info about those at:
Altera Cyclone V
Xilinx Zynq
You maybe able to use an external host controller but then you have to connect it to your FPGA and that is usually requires a lot of IOs and those modules are more expensive than buying a Zed board ($395) or Cyclone V board ($450).