Saturday, August 13, 2011

Interesting discussions about Linux

The post itself is not that interesting and kind of dumb. But the comments sections are much more interesting. The best comment is from "linuxlover" on August 12th, 2011 at 11:05 am.

I use both Windows and Linux and kind of neutral. Windows has many problems. Linux has many problems as well. Linux has many advantages. Windows has many advantages as well.

********* Quote "linuxlover" *****************
Advantages of Linux
1. App bugs will get fixed when a new student takes over from the one that graduated and got a job.
2. The packaging chaos will get fixed, since the Darwinian process works (only needs a few million years).
3. The desktop chaos will get fixed for the same reason.
4. Linux distros will stop competing with each-other and start focusing on Microsoft.
5. Ubuntu’s 80,000 open bugs will make them releasing when ready instead of every 6 months.
6. Instead of dozens of half-finished programs for a given application, there will be 1-2 really excellent ones.
7. Unity may get modified to be effective for monitors over 800 pixels.
8. Compiz may get fixed for high-speed window updates.
9. A serious standards body will develop and enforce sensible standards (packaging, desktop, libraries, binary API, GUI API).
10. If you are having problems, you can choose from hundreds of distros that will have different problems.

I actually use and enjoy Linux, but let’s face the problems honestly.

OpenOCD 0.5.0 release Windows binary download

OpenOCD 0.5.0 has been released. Here is the News.

Source zip archive or tar ball can be downloaded from SourceForge.

Windows binaries (32bit and 64bit, cross build under Linux with MinGW-w64 project's compiler) can be downloaded from Freddie Chopin's website.

You can also use my test build which is native Windows build using 32bit toolchain.

Take note due to GPL licensing reasons, these Windows binaries are linked against libusb-win32 and libftdi and not the proprietary FTDI D2xx library.

Tuesday, August 2, 2011

USB CDC-ACM is really meant for USB Modem

Many users use USB CDC-ACM for virtual com port usage. It
is supported under Windows by the usbser.sys driver and
also works under Linux and Mac OS X and probably other OS
as well.

In reality, CDC-ACM is really meant for modems.

"3.6.2 Abstract Control Model
With an Abstract Control Model, the USB device understands standard
V.25ter (AT) commands. The device contains a Datapump and micro-controller
that handles the AT commands and relay controls. The device uses both a
Data Class interface and a Communication Class interface."

Microsoft states that usbser.sys is really meant for
USB modems.

"usbser.sys is only good enough of a virtual serial port implementation to
enable it to be used as a modem".

Apple even insists that it is for network device (a USB modem is
a networking device) and insists to bring up the network configure
dialog. Here is an heated debate thread in Apple USB mailing list.

And Linux will issue a warning about a USB CDC-ACM device
if it is not a modem.

918 call_management_function = buffer[3];
919 call_interface_num = buffer[4];
920 if ( (quirks & NOT_A_MODEM) == 0 &&
(call_management_function & 3) != 3)
921 dev_err(&intf->dev, "This device
cannot do calls on its own. It is not a modem.\n");
922 break;