© Earth Vega Connection, 2003 |
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| March 17th 2004 |
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A new bugfix release is out. Some users reported
strange behaviour of the driver, sometimes leading to serious crashes (BSOD). Thanks
to Claude Voit I was able to find the cause of these problems. It appeared that system
exclusive messages of certain sizes would lead to data loss and memory corruption. Because
of the relatively rare occurence of this problem it was missed in the test phase.
On top of this I improved the handling of so-called system realtime messages and reduced
the memory usage of the driver considerably.
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| January 06th 2004 |
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Sometimes you want to do things too fast. The update I released a little more
than a week ago appears to have an annoying problem. You may have encountered it if you
have a keyboard that emits something that is called 'active sensing'. The updated driver
does not handle active sensing well. It causes lost data.
Fortunately it did not take me long to fix, only this time I wanted to test it thoroughly
before releasing it. So here is the new version 2.6 of the 8 Port SE DirectMusic driver. It
passed my stress test flawlessly. Grab the update patch here.
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| December 27th 2003 |
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There is a new version of the DirectMusic driver out. Registered users
can download a free update patch here.
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| October 18th 2003 |
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I added an installer program to the demo driver, making it a lot easier to install (and
uninstall). I am removing part of the installation manual from the web-site. It's not needed anymore.
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| October 10th 2003 |
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I discovered a fairly serious bug in the demo driver when running on Windows
XP. If you open an input when the driver is active, the system will freeze
when it receives input after the time-limit has passed.
As I do my development on Windows 2000 and the bug does not occur on that OS, it
managed to escape my attention all this time. I have put a new version of the demo up that
fixes the problem.
This bug applies only to the demo driver and happens only on Windows XP. The full version
drivers don't suffer from it.
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| September 30th 2003 |
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It has been announced in this same place but finally it is there.
The 8 Port SE DirectMusic Driver was released today. Registered users of the 8 Port
SE WDM Driver received an email notifying them of the special upgrade offerings. If you are
a registered user of the WDM driver and you did not receive the mailing, please contact me and
I will send it to you.
The DirectMusic driver will replace the WDM driver. The WDM driver will from now
on only be available by special request. If for some reason you prefer the WDM driver to the
DirectMusic driver you will still be able to order the WDM driver.
The new DirectMusic driver is fully backwards compatible with the WDM driver. No functionality
is lost, only new features are added. Technically speaking the DirectMusic driver is even still
a WDM driver. To avoid confusion and to keep the old and the new driver apart I use these
names to refer to them.
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Uses DirectMusic technology for faster hardware access
Multi-client capability
Easy renaming of individual inputs and outputs with PortNamer utility
New installer application makes installing and uninstalling the driver a breeze
Read more about DirectMusic and the driver here.
The 8 Port SE is a MIDI interface that connects to the parallel port of your PC.
When it was released it came with a driver for Windows 95. This driver also works on Windows 98.
There also exists an NT driver, released in 1998. Some people claim to have been able to get
this driver to run on Windows XP. I tried this myself but it would not install on any computer
I tried it on.
Since the release of the NT driver, no new drivers have been released for this device. Until now.
You need a WDM driver if you want to work with Windows 2000 or Windows XP. WDM stands for Windows Driver
Model which is the standard for drivers for these operating systems.
There are not many MIDI interfaces that connect to the parallel port for which WDM drivers have been developed.
Most MIDI interfaces produced nowadays connect to your PC via USB. I personally think that USB in its present form
is not particularily suited for connecting such realtime devices. The main reason lies in the WDM driver model
itself. The WDM model is a layered model. Messages from and to a device have to pass through these layers. The more
layers the slower the communication between device and system will be.
A developer writing a device driver for a USB device will not write the various layers himself. Many of the layers
in the communication are part of the operating system. The Windows operating system was never designed for real time
operations. It was designed mainly for business applications. USB was designed for connecting printers and scanners
and the like. A printer doesn't mind waiting for half a second. For a MIDI interface such a delay is disastrous.
Interfacing through the parallel port is much more straightforward. The operating system provides for in-between
layers but they can be easily bypassed. This way a driver can talk straight to the hardware and thus provide faster
handling of MIDI data.
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