How to create a virtual MIDI device - port

I have to write an application (like a step sequencer or arpeggiator) that sends MIDI note to a generic DAW , so I think that only way to implement such thing is to create a virtual MIDI device that should be recognised as a MIDI input/output interface by the OS.
I was wondering if this could be developed using Portmidi or if I need something more complicated.
OS X support is a must, Linux and Windows support is a nice to have.

Portmidi's design is based on the Windows MIDI API, which does not allow applications to create virtual ports (without installing a separate driver).
On OS X, you can create a virtual port with MIDISourceCreate; on Linux, by creating a port with the (SUBS_)READ/WRITE flags.
If you want to use a portable library, try RtMidi, which supports virtual ports on all platforms that have them.

For Windows, check out the virtual MIDI driver written by Tobias Erichsen. While he hasn't published the API, if you e-mail him he will work something out with you. It's very simple to work with and allows creation of MIDI ports directly from your application.

Related

What is the most suitable virtual machine software for sharing hardware ports (COM, LPT etc) at register level?

I'm using Delphi to develop real-time control software and over the last couple of years I have done some work running older Windows installations under Microsoft's VirtualPC and it works fine for 'pure software' development (i.e no or limited access to the outside world). Such tools seem able to work with network connections but I have to maintain software which performs I/O via the parallel port (via a device driver). We also use USB I/O. In the past I've liked Microsoft's virtual tools because it takes time to install a new operating system and then (in my case) install Delphi and a load of libraries and components to provide development support. In these circumstances I've not been too bothered by my lack of access to the low-level I/O ports.
I want to up my game and I'm happy to pay for a good virtualisation tool IF I can have access from it to the outside world, i.e I want to be able to configure it to allow access to my machine's parallel port and com ports in the same way as if it was running natively. This access has to be able to expose the parallel port in register terms, i.e to 'see' the port at address $03f8 for example and to support I/O operations of those registers (via the appropriate kernel access) as my Windows 7 64-bit installation is able to do.
I see that there are a number of virtualisation solution out there now but it's quite hard to acertain the capability of each at such a low level. Does anyone have any experience or knowledge in this area?
The VMware products would be suited best for this. You can add virtual serial and parallel ports and forward them to a physical port on the host, or even to a file or a named pipe.
You can also connect any USB device that is connected to the host machine.
This works with VMware Workstation, but might even work with the free VMware player too.

How does Proxifier work?

As you know Proxifier is a program that allows network applications that do not support working through proxy servers to operate through an HTTPS or SOCKS.
It can handle any transmission from running applications. I want to know how it can do this and how I can write one like that.
FreeCap is your way to go.
It's released under GNU General Public Licence and written in Delphi.
A socksifier defines a dynamic library with the same functions as the OS socket layer, but defined in such a way as to use a socks proxy. The program being socksified uses that library instead of the OS-supplied one for its network communication.

How can I access a game controller via USB?

Problem
I am working on modifications to one of my applications that communicates with a telescope.
One of the most annoying problems due to nothing else but reckless poor design, is the GOTO controller and its keypad.
If anyone of you remember the Sinclair Spectrum you know what I mean. As well as the rubber keys, the crucial keys for guiding and slewing the telescope are awkward to locate when your eye is trying to adapt to the view.
All it takes is the wrong key and you spend another 30 minutes or so re-aligning the telescope.
Workaround
My solution is a game controller such as a wingman, it fits neatly into your hands and is easy to locate the buttons. Also there is no risk of reseting the mount.
Question
My question is this, how does Delphi interact with game controllers because tthere is no mention in the documentation? Otherwise how do I access a gameport when it is connected through a USB dongle?
Working with the game controller is part of the Windows API. JEDI's JVCL has a Human Interface Device (HID) constroller (TJvHIDDeviceController) component that does what you want.
Delphi applications running on "NT" line operating systems (NT, 2000, XP, Vista, 7, 2003, 2008...) can't access hardware devices directly. Only drivers can, because the I/O ports required to access them can be accessed only by code running at the right IOPL level (which is 0 in Windows). There are some generic drivers available that open any I/O port (thus creating a security hole) that user code can call.
But tt's far better to rely on device drivers, and use the HID API to interact with them. Windows will recognize most older devices (like the serial/game port Wingman), while newer USB ones or use the standard drivers that come with Windows, or come with their own. Once the system recognizes the devices, you can use them in a standard way with no need to dig in the low-level details.

Writing data to I/O address

i have a device (cash drawer) and i would like to directly communicate with the device. I know that its on address f1. Also openbit is 01.
As i've understood so far, i'd need to send 1 to memory address f1 and the cash drawer should open. Though using asm, i get access violation. Then again i've read that windows does not let you communicate directly to device i/o addresses (need to use win). What would be the correct way to send the data to that address.
Note that i cannot use drivers, because i can't communicate with the driver inside my application.
Op. system is win7.
Thanks in advance!
There was a library called inpout32.dll that allowed direct port access you can find it here
http://logix4u.net/Inpout32.dll_Discussion/write_DELPHI_for_inpout32.dll.html
But i don't know if supports windows 7.
In addition to the excellent suggestions above, check out this delphi code for writing and reading I/O. We have used the GWIOPM to do what you are asking, but note that it will be ok for 32-bit versions of Windows up to W7 etc (as is the case for most 'free' drivers). For 64-bit Windows you need a signed kernel driver. For this there are few things available at the moment. We had to write our own.
Why can't you communicate with the driver from your application? It's the best way for ring 3 application to talk with hardware in a safe manner.
However, if you really insist using drivers, you can try going to ring 0 and do direct access. It's much harder than in previous Windows versions (XP and before) but it's possible. I haven't done it myself since I don't have Windows 7, but you can try asking in asm programming forum anywhere.

Debug COM port read/write using software/virtual COM port and console/terminal on the other end

I have a Delphi application that reads/writes to a COM port connected to a large hardware device, so I don't usually have the hardware available during development. That said, the communication protocol is fairly simple, so I can generally do the development and have someone onsite test it, and it usually works. Occasionally I run into a harder problem, though. To solve this, I'd like to setup a virtual COM port where one side of the COM port is my application and the other side is a very simple COM port debug console (similar to the old modem terminal programs), where ASCII commands my app sends are logged onscreen and I can type in some ASCII command to send back to my application to simulate the hardware device. I've been unable to find any tools that provide a virtual/software COM port and a console/terminal to debug with. Does anyone have software suggestions and steps to set something like this up?
The software/virtual COM port and terminal need to support Windows 7 64-bit (or Vista 32 if necessary).
I'm doing something similar with paired virtual COM ports created by
http://com0com.sourceforge.net/
I'm using Advanced Virtual COM Port and I'm quite happy with it. Not free, but works like a charm - even with Win7-x64.
Can't you just insert a redirector at the lowest level of your application which will pop up a console instead of writing data to COM? Should not take long.
I can't vouch for it, but sounds like something like this is what you're looking for. http://www.windows7download.com/win7-free-virtual-serial-ports-emulator/yarqmowu.html
I have used Eterlogic's Virtual Serial Ports Emulator successfully for exactly this on a laptop with no serial ports. It's a bit easier to set up than Com0Com, which I have also used. It's also useful for serial port spying if you need to reverse engineer any communications
The 32-bit version is free, the 64-bit version is currently $25. Try it out on Vista32 to see if it does what you need.
I use Com0Com for this purpose, but I don't know whether it works with anything more recent than Windows XP.

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