im trying to interface a Gramin usb GPS to get the coordinates in a visual basic project, but i dont have an idea how to accomplish this, anyone point me out in the right direction please?
If the Garmin unit uses an RS-232 (standard serial) interface, then its USB driver probably implements a virtual serial port that you can open using the MSCOMM control.
Check that by opening the Hardware Manager and see if there's an extra port, maybe even labeled 'Garmin', while it's plugged in.
There are simple, standard text protocols used by GPS units. As long as no other app has the port open, you should be able to open it in VB and capture the output with a little experimenting for baud rate, etc. 4800,8,N,1 is a good place to start.
Related
I have a custom ESP32-S2-based circuit board with USB-C which does not have a USB-serial converter IC like a common dev board might. On this board, USB(-) is on GPIO19, and USB(+) is on GPIO20. USB works great for powering the board and for uploading firmware.
The board works well and I have access to good old-fashioned serial console via a USB-to-logic level serial interface, but it would be nice to be able to get serial out to USB along with the firmware upload (like a dev board).
I’m using PlatformIO in Visual Studio Code, and writing with arduino-esp32 rather than ESP-IDF.
I understand by these instructions from Espressif that when using ESP-IDF I can configure log output to go to USB CDC rather than UART, and this has been done successfully on my custom board. But I would like to be able to do this without having to switch over to ESP-IDF.
I’m presuming that one of the partitions that PlatformIO is building for me is this configuration with some nice common sense defaults, but I can’t see how I might alter those defaults to do what I’m looking for.
Any thoughts or pointers?
I have an usb device (pole display), which i don't have driver for.
I installed generic usb driver and opened the port for sending(I use bulk transfer) data to device.
With usb monitoring software i see my data gets to device, but nothing much happens on device side.
The device commands(ESC/POS) work when transfered over (virtual) com port, but not over usb port.
Shouldn't device process commands the same way regardless connection type (com vs usb)?
How can i figure out what commands work with the device (for example, if i send some text, i want it to show on display)?
Any help is appreciated!
Look at the USB descriptors the device reports in order to determine its class. If it is a custom device and not a standard class then you'll likely not be able to work with it. There is a big difference between old RS-232 COM protocol and USB. USB devices can have multiple configurations and endpoints, each responding to data in different ways. Many classes exist and are pretty standard (CDC-ACM is typically used for virtual serial ports.) However, it's not uncommon for device manufacturers to include OEM specific configurations and endpoints which can be used for their own custom interfaces, firmware loading, etc.
Is there any initialization data transmitted through the COM port when connecting the device? The device surely can treat COM and USB different, but another possible thing that goes wrong is that the device needs to hear some sort of "I'm going to start sending commands"-signal from you first, and that signal may be different between COM and USB.
So what I would recommend is first (if you have not done that yet) see what data is sent to initialize the COM connection, and if that doesn't have an obvious USB counterpart, connect it to a PC where you do have drivers (assuming that is available somewhere and somehow, which is possible if e.g. you ask this due to OS incompatibility) and see how the connection is initialized there.
If the first doesn't work and the second is unavailable to you, then I'm afraid there's little I can do to help you, since it's usually not visible for you what commands the device wants to hear other than by guesswork, documentation, or comparing to similar devices where you do have that data available.
I have an Arduino application talking over USB to an application on Windows 8 using the MAVLINK protocol. The connection appears as COM3.
Is there a Windows application that can spy on this connection and display the traffic going in both directions? Raw bytes are fine, I don't need the protocol decoded.
You could log serial port activity using Portmon. (Edit: You need to first connect to the local computer via the Computer menu, and you must start capture on the port before a program opens it.)
You may not want to log USB traffic. Such a log would include a lot of extra information relating to the USB to serial adapter which is providing COM3. Portmon would only give you the bytes transferred over COM3, and the Mavlink protocol is entirely contained within that data stream. If you're sure you want to log all USB traffic to and from that device, then I recommend SnoopyPro. In Windows 7, you need to run it as administrator.
If you can use Windows XP in your environment, USB sniff should work for you. If you need something more powerful (and are willing to pay a fee for it) then USBLyzer might be a viable option.
The answer is SnoopyPro, and you can download it at:
SnoopyPro Sourceforge
This tool allows you to get USB information and also USB communication data. I used it in the past to know how a USB device worked in order to do its driver on Linux. I used this tool as a sniffer.
Basically, SnoopyPro allows you to intercept, display, record and analyze the USB protocol and all transferred data between any USB device connected to your PC and applications. It can be successfully used in application development, USB device driver or hardware development and offers the powerful platform for effective coding, testing and optimization.
I have developed a USB device that communicates with linux over a simple but proprietary interface and some custom Linux drivers. My goal is to port this to Windows without writing windows drivers. What I would like to do is find an open source or inbuilt class driver for windows that would look like a COM port in Windows. Then I would tailor the embedded software to match what ever protocol and descriptors the virtual COM port expects to see.
The idea would be that I could plug my device in to a Windows machine and a relatively high speed COM port would appear with out me having to develop Windows drivers for it.
I have been looking at the USB CDC (Communications Device Class) documentation and it looks promising, but I don't know which sub interface would be best to use so that it would show up as a COM port.
Has anyone here done any work like this before or could provide some insight?
Specifically:
Are there virtual COM drivers "built in" to windows or would I need a 3rd party driver.
Which CDC sub class should I use for simple RS232 emulation (No need for modem AT commands, etc)
Is there a better option to do what I am trying to do.
Thanks
There is a USB-to-serial driver built in to Windows that will do what you want. It is called usbser.sys:
http://support.microsoft.com/kb/837637
You will have to write an INF file and distribute that to your users, but that will not be too hard because it is only a few kilobytes of text and you can find examples online.
I'm not aware of any great documentation for this driver by Microsoft, so my advice would be to find some other device that uses it, such as Pololu Wixel, and copy what they did.
Here are the device descriptors we used and the special control tranfers we had to implement:
https://github.com/pololu/wixel-sdk/blob/master/libraries/src/usb_cdc_acm/usb_cdc_acm.c
You can see our INF file, wixel_serial.inf, by downloading the software and looking in the drivers folder:
http://www.pololu.com/docs/0J46/3.a
(There are other files in there that are not necessary for you.)
You can also look at the Arduino Uno because they use the same driver.
Whatever you do, please don't use our USB Vendor ID in your product! You need to get your own.
Update: In Windows 10, you don't need an INF file anymore because of the new usbser.inf driver that comes with Windows.
If you are using a UART you can easily interface it to a FTDI USB chip like http://www.ftdichip.com/Products/ICs/FT232R.htm or a Prolific like http://www.prolific.com.tw/eng/products.asp?id=59
For development, prototype and testing I have half dozen of these laying around http://www.pololu.com/catalog/product/391
I connect it directly to the UART pins on AVR and 8051 micros.
I have a Arduino app that needs to talk to my PC across the USB (Serial) connection. I have this bit of code that I lifted from the Arduino Playground at
http://arduino.cc/playground/Interfacing/CPPWindows#VisualStudio2008
this->serialPort1->PortName = "COM5"; // Replace with your COM port!
this->serialPort1->Open();
this->serialPort1->Write( "7" ); // In the future, you'll expand on this
// to write your custom data to the board
this->serialPort1->Close();
My question is how does one determine what COM port the Arduino USB cable is attached to?
There are several ways you can approach this.
The most obvious is that you simply make your application configurable and tell it which serial port to use. The port name should never change, unless you have other processes on your machine allocating virtual COM ports such as Bluetooth drivers.
A second option is that you can do what the Arduino app does and scan the serial ports on the system looking for the hardware. Since you are using the CLR, System.IO.Ports.SerialPort.GetPortNames() will give you a list of all the serial ports on the system. (You can also get this from the registry.) Then you can enumerate through them and check the status of the pins to see which serial ports have devices attached. You should probably include in your sketch a way to query the Arduino so that you can send it a command and have it give a fixed response. This would allow you to discern your application from other serial devices such as modems.
There is a third option which would involve figuring out where the FTDI driver stores its configuration information in the system/registry and going from there. This is a bit more involved, so I can't give any information on if this approach is even viable.