I have a Korg NanoKey which I'd like to use to control a simple synthesizer I've designed on the Arduino platform. (I have an Arduino Uno.) Basically, I don't care about MIDI, I just want to read what note the keyboard has pressed down, but if MIDI is the only way I can do that, then it's okay with me. So my big question is, how do I do this? I haven't been able to find anyone else on the Internet who has already done this.
But more specifically, I see two challenges: First, I'd like to plug my NanoKey directly into the Arduino's USB port, but then I'm wondering if the Arduino would provide the necessary power to the NanoKey. Second, I'm not sure what protocol I would be reading. Can I just read MIDI signals as described in this tutorial?
I don't want to curb your enthusiasm but what you're attempting might be a bit hard basket. A USB system consists of a host controller and one or more peripheral devices. It's the host that controls traffic flow to the devices which means that devices can't transmit data on the bus without an explicit request from the host controller.
I'm not familiar with either the nanoKey or the Arduino platform but I'd be fairly confident that the nanoKey is a USB "device", normally connected to a computer which would act as the host. So what you would need for this system to work is for the Arduino to act as the host when communicating with the nanoKey. The Arduino schematic shows that the Arduino Uno uses an ATmega8U2 for USB coms. Unfortunately the ATmega8U2 is a USB device, so you've got two peripheral devices but no host controller to facilitate the transfer of data between them. You'd be better off using a development board for a micro that provides either USB Host or USB On-the-Go.
I opened up a Korg Nano controller yesterday and was surprised to discover that there's an AVR mega32 inside. It would be a significant undertaking, but with a bit of work you could probably work out the schematic and reprogram it yourself using their programming header breakout. You might not end up with much more functionality than you've got this other way, but it would be very educational.
I agree with the Jono - you are biting off a lot - it might even end up easiest to hook the keys up to the Arduino directly - tearing out the electronics and figuring out a way to multiplex the keys into a single channel without losing polyphony (resistor 'ladder' maybe). I any case, good luck. Amusingly, you'd making an analog keyboard to plug into a digital synthesizer.
Quick and Dirty Arduino MIDI Over USB demonstrates how to send/receive MIDI out over USB, but unfortunately, this probably isn't any help for what you are trying to do, since he's found a way to send and receive MIDI signals from a USB host, not act as a USB host himself - the opposite of your problem. However, I thought perhaps it would be of use, if you ever wanted to control your device from a computer.
As mentioned in the other posts, you would need to use a separate chip to provide the USB Host interface. Here's a great guide to using the USB Host shield by Circuits#Home to interface with an Akai LPK25 (USB Midi Keyboard).
http://blog.makezine.com/2010/11/30/usbhacking/
The Arduino sketch is provided, so you should be able to try it out, however debugging the USB Host connection could get tricky real fast if it doesn't work out of the box.
Related
I recently acquired a Microchip EVB USB7252. I can use it as a USB hub. There are some pins on the board, and I have been looking for ways to use these as an interface between my computer and other devices (preferably my LCD screen).
So I got the IDE + compiler that is supposed to work for this product (MPLAB), but I could find no way to choose my model and get the correct target board.
I was hoping anybody (with likely more experience than me) could steer me in the right direction here. My only previous experience with dev boards is Arduino, where boards show up automatically as COM ports in the IDE. My ultimate goal here is to connect my peripherals to USB without using virtual COM-ports.
https://www.microchip.com/en-us/development-tool/EV33X03A
You can Try The IDE call "MPLAB" you said
and i think arduino CANT use "Microchip EVB USB7252"
So Try it And Good luck
It's a long way because USB is not easy protocol. You need to read USB specs first. Take a look at http://www.usb.org. Generally USB communicate between host and devices. There is special protocol used in this communication.
Perhaps the easiest way to do this will be using Linux and libusb or similar library. When you achieve some experience with this protocol you may be trying to write your own USB driver. I could also recommend to analyse some USB stacks like in Linux or in U-Boot one first.
If you have possibility then I'd also try to use some hardware/software USB protocol analyzers for some overview how does the communication look like.
I'm trying to configure/write VHDL code that would let me output or input data from the USB port on a Basys3 FPGA board. Problem is I have yet to found any threads or questions that talk about this topic.
The nearest thing to an answer I've found is this:
Provide input data to FPGA using USB
and it does not contain what I'm looking for.
Any clues anyone¿?
The Basys3 board has a usb-uart bridge chip as described in the reference manual. This will appear to a PC (or any device with a usb host and the appropriate usb-serial drivers) as a virtual com port. Sending data to and from a PC com port is quite easy.
You will need a uart implementation on the FPGA. There are lots of example designs on the web. One way is to implement a soft core microblaze processor with a uart peripheral in the FPGA. This example looks like it includes foundation for the functionality you desire.
The simplest implementation from the PC side is using a terminal program such as putty, Tera Term or realterm. Most languages include com(serial) port libraries or bindings. This type of interface tops out at a raw bandwidth of around 3-12Mbits per second depending on the drivers and implementation.
Read the manual for the Basys 3 board. It will explain how you can interface with USB devices plugged into the USB port. Be warned, however, that your options are pretty limited.
Short version: if you plug in a USB mouse or keyboard, they will be exposed to your design as an emulated PS/2 device. USB storage devices can be used to configure the FPGA. Other devices are not supported.
I have a custom ps2 keyboard(8x8 matrix) interfaced with AT89C51ED2 microcontroller, now I need to change it to USB interface. I have been studying about the basics of USB HID class communication(USB HID class specs, USB complete, Beyond logic) and have come to know little bit about the theory behind it.
But I am not able to understand the firmware part, I read a demo keypad application by Microchip which had given a sample source code, but I am not able to understand in the code how data(key pressed) is sent to the IN endpoint and how the host reads that through polling. I know that endpoint is a buffer from which data is sent to host, but Is it one of the registers of the micro-controller and how do I use it in my code?.
And I have been searching the suitable micro-controller with USB support, but no supported demo's are available, any suggestions will be helpful
The AT89C51ED2 datasheet does not mention hardware support for USB, so the answer is no: an endpoint does not correspond to a hardware register. Instead, an endpoint would refer to some software buffers in the RAM of the chip, and some data to keep track of the endpoint's state. Every bit of every USB packet must be handled by the firmware of the device, and endpoints are an abstraction that live entirely in the firmware of your device.
Note: I am assuming that the keyboard doesn't have some kind of USB interface chip, and that the data lines of the USB cable connect more-or-less directly to the microcontroller.
If you can't find the source code for the keyboard, you might look into using an open-source AVR software USB implementation. Here are some useful links:
https://www.obdev.at/products/vusb/
http://www.fischl.de/usbasp/
Please note that you are undertaking an advanced project, and if you are not familiar with AVRs, USB, microcontrollers, reverse engineering, and embedded development/debugging, it might be useful to start with something simpler first.
Further to this question, I'm looking for a device that will allow me to connect two USB hosts, while still being fully programmable. I would like something that can do the following:
Masquerade as an arbitrary USB device
Take input from a PC and do nothing but pass it on to the other host.
I've been looking for a microcontroller (preferably pre-assembled) that will allow me to do this, but have so far come up blank. Does anyone know of a controller (preferably cheap) that will allow me to do this?
Take input from a PC and do nothing but pass it on to the other host.
This is non-sensical from a USB perspective. USB is a host-based protocol: a device will never send data unless a host requests it first. Keep in mind here, 'host' and 'device' have specific meanings here within the protocol itself; you can think of a 'host' as the master and the 'device' as the slave. These roles are baked into a USB controller. There is no way to convince a standard USB controller in any given PC or peripheral to swap roles. There are add-in cards for PCs that are USB device controllers (making your PC act as a device), but 'cheap' is not a word I would use to describe them.
What you really are trying to do is create something that is a USB device to device bridge. So, alright, you need to have two USB(2.0) device controllers (maybe not that expensive, some micros already have to on-the-go controllers). Then you have to get them to pass something meaningful to each other. That's really hard because, as I mentioned above, hosts must tell a device to send data, and can send data to a device whenever it wants. Assuming a game controller shows up as a HID device (assuming the console doesn't listen for some weird, custom descriptor, and use some weird, custom protocol), interrupt pipes will be used to transfer data. This pipe is guaranteed to be polled at some minimum rate. So you have the console requesting data at some rate, which is not fixed, and a host-as-gamepad sending data at some rate. It's going to impossible for the two to sync up, so you'll need some kind of decent sized buffer on the gadget you're trying to create, which adds more $$ and more complexity.
USB is also pretty fast. In high-speed (USB2.0), frames are 125 microseconds long. That means you have to be completing requests at around 8KHz, which seems slow compared to the clock speed of a microcontoller, but keep in mind you have to be doing everything else at once. I'm not sure if there's a hobbyist-level microcontroller that's going to have everything you need, especially one for which you don't need to roll your own USB stack.
Try this chip -> FTDI 232 they are protocols chips, it will translate the data to i2c, spi, serial, whatever u want. nice, easy and cheap :) . FTDI firm, have even better ones (vinculum), with otg and everything u need but I would start with the FTDI232. U just need to use your favorite uC to do the work u want. ... on the other hand, u have to do a little board, maybe some soldering, :). good luck!
You will need $$$$ in equipment and $$$$$ in development work to achieve things the way you imagine. You should better tell us what do you want to emulate, and take a look here if someone has already done it for you. If not then use LUFA library with some bigger USB AVR that can behave as USB host and connect two of them (one as USB guest and the other as USB host) via some other protocol (I2C/SPI/UART).
In the meantime there is a great solution for this Problem. Using the FaceDancer Library together with one of the boards supported by this great piece of software (i.E. GreatFET One) you get exactly what you want:
The GreatFET One has two USB connectors: the first one is used to simulate ANY kind of USB Device, while the second one is used to forward all requests/responses received/send via the first connector.
Of course this tool requires that you know the USB protocol of the device you want to simulate. Although there are some code samples you still have to know what you are doing as soon as you customize them.
I'm planning to build a USB device that has buttons that some software needs to respond to, and indicators that the software needs to control. I'm new to USB, so I'm looking for any pointers that will get me started.
When I did some USB development a while ago, I found the information at USB Central extremely valuable.
For low bandwidth requirements, you can use something like the FT232R which is a single-chip USB serial implementation. The FTDI drivers are readily available and make the device appear as a regular serial port to the host computer. This is orders of magnitude easier than rolling your own USB implementation (for either end!).
Kinda vague, but in the past I've done a little bit of USB development. The easiest stuff tends to be HID related device as the subset of USB used to commincate is very to implement on both sides. There are hardware devices which are essentially stubbed out to work with HID, you just customize some circuity and go.
The USB standard is actually quite readable. Though it might be a bit overkill if you just want to create a simple device. You could probably get something like this, which is basically an 8051 controller with a USB connector together with firmware and a DLL.
Checkout WinDriver, which is a commercial multiplatform tool what give you easy way to implement usb drivers in user mode, source code compatible between Linux and Windows.