During the next couple of days I’ll be testing out a couple of PCI WiFi Cards. The only part of this I’m not really looking forward to is the LEAP configuration that is required for this project. If things go well I’ll let you know the model numbers of the cards tested and the outcome of the tests.

Last week was spent in an automotive factory performing a software / hardware upgrade (5 days away from home, hence the lack of updates to the site). All went well eventually, another successful Linux upgrade.

UPDATE 1:

Netgear WPN311 – madwifi-ng ==> Netgear RangeMax WPN311 Wireless PCI Adapter
Linksys WMP54G – rt61 or ndiswrapper ==> Linksys Wireless-G PCI Card WMP54G – Network adapter – PCI – 802.11b, 802.11g

Both of these adapters have been tested using standard 128bit WEP encryption (NOT RECOMMENDED !!!). Further testing is required for reliability and signal strength. I would guess that WPA2 would be fully supported by these devices, but I have not had the time to test this out.

UPDATE 2:

LEAP configuration / support has so far been unsuccesful with these two devices.

Last year we were in need of some extra storage space, ideally we required this to be a shared resource so everyone could view the files stored and keep backups of important documents. So after searching around the internet we decided upon a DNS-323 device and two 1TB SATA hard disks.

D-Link D-Link 2 Bay Network Storage Enclosure

The DNS-323 has a Gigabit Ethernet port and a USB port on the back of the device. The USB port should be used to enable a printer to be shared over the network. The network printer support was not required, and after looking around the net came across a nice hack that would allow another USB hard disk to be attached to the device (more lovely networked storage). We connect to this device as a standard network share (using both Windows and Linux systems). You may also use FTP if you require, and it supports UPnP AV Server.

Even though the unit supports various RAID options we decided upon JBOD to take advantage of all 2TB of storage. This unit has been in extensive use for close to a year now and has seen no faults (touching wood). It has been powered up 24/7 for most of this time and I’m impressed with it’s perfomance too. A great device over all well worth a recomendation =))

I needed to upgrade a couple of WiFi systems at home the other week and opted for a couple of USB WiFi dongles (Gentoo is used as the Operating System on these systems using a 2.6.25 kernel):

D-Link Wireless N USB Mini-Adapter – DWA-140 (H/W Ver: B1 F/W Ver: 1.00)
Belkin N Wireless USB Adapter – F5D8053uk (Ver: v3000uk)

Both of these adapter contain the Ralink RT2870USB (rt2870) chipset. So if you are not worried about doing some kernel module compiling then simply download the required driver from the Ralink website. Then uncompress the archive and change directory to the driver. Now for the Belkin Adapter you will need to add a single line to the code (VID/PID):

Add the following to the line to the include/rt2870.h file:

 {USB_DEVICE(0x050D,0x8053)}, /* Belkin */             \
+{USB_DEVICE(0x050D,0x815C)}, /* Belkin F5D8053 */     \

To enable the use of wpa_supplicant you may wish to edit the ‘os/linux/config.mk’ file as follows:

HAS_WPA_SUPPLICANT=y
HAS_NATIVE_WPA_SUPPLICANT_SUPPORT=y

Then type ‘make’, when the make process completes successfully type ‘make install’. You should now have the required kernel module installed on your system. There is a configuration file for this module, located within the /etc/Wireless/RT2870STA directory. Follow the directions given in the modules README file when editing this file (a copy of my configuration is located below:

RT2870STA.dat

I have this working with WPA2 and running at around 300Mb/s. Out of the two modules the D-Link Adapter has performed slightly better than the Belkin, and it was slightly cheaper.

While on the subject of WiFi and Linux, I also have a Belkin N Wireless Express Card Adapter used within a Laptop. This is a Belkin F5D8073 (ver. 3000x):

This works with Gentoo and the Ralink RT2860PCI (rt2860) kernel module. There were no changes required to the source when using this module, although your kernel must be configured with PCI Express support. There is a configuration file for this module, located within the /etc/Wireless/RT2860STA directory. Follow the directions given in the modules README file when editing this file (a copy of my configuration is located below:

RT2860STA.dat

It is very easy to keep your Gentoo install up to date, simply use the following commands (not more than once a day):

emerge –sync
emerge -uavDN world
etc-update
revdep-rebuild

There you go nice and simple, no need to upgrade when your distro releases an updated DVD/CD.

Keyboard Shortcuts

Here are some very useful keyboard shortcuts for use with Microsoft Windows.
The Windows Key is the key with the Windows logo printed upon it (left side of the space bar).

Windows Key and R = Run dialog box.
Windows Key and F = Find dialog box.
Windows Key and Break = System Properties dialog box.
Windows Key and E = Windows Explorer.
Windows Key and D = Minimizes all Windows. (Do the combination again to Restore all Windows.)
Windows Key and M = Minimizes all Windows.
Windows Key and Shift and M = Restore all Windows after the above key combination.
Alt and Tab = Loop though currently running programs.
Alt and F4 = Closes window with current focus.
F2 = Rename an item.
F3 = Find a file or folder.
Shift and Del = Delete immediately without send the item to the recycle bin.
Alt and Enter = View item properties.
F5 = Refresh.
Ctrl and A = Select all.
Ctrl and ESC = Display Start Menu.

Ctrl while dragging the file = Copy File.
Ctrl and Shift while dragging file = Create Shortcut.

Common keyboard Shortcuts for Windows Applications -

F1 = Help (and we all need this one at sometime).
Ctrl and Z = Undo last command.
Ctrl and X = Cut.
Ctrl and C = Copy.
Ctrl and V = Paste.
Ctrl and B = Bold.
Ctrl and I = Italic.
Ctrl and U = Underline.

These are the most commonly used keyboard shortcuts, below are a couple more not so widely used.

Alt and Print Screen = Copies the current screen display to the clipboard. (Screen capture.)
Alt and Enter = Toggles a Dos prompt between Full screen and window view.
F3 = Redo last command typed in DOS (or a DOS prompt window).
F1 = Redo last command typed, character by character in DOS (or a DOS prompt window).

This is not a complete list of keyboard shortcuts, but these are the most commonly used by far.

FILE *file_ptr; /* declare a file pointer variable */

Recommended way to open a file -

if ( (file_ptr = fopen(“Filename.dat”,”rt+”)) == NULL )
printf(“Error opening file\n”);

Reading from the file -

char *fgets ( char *str, int number, FILE *stream );
/* Returns EOF on end of file or an error occurs */
eg. fgets( my_string, 80, file_ptr);

int fscanf ( FILE *stream, char *conversion_string, arg_list);
/* Returns the number of successful conversions */
eg. fscanf ( file_ptr , “%d %d %d”, &int1, &int2, &int3);

Writing to the file -

int fputc ( int character, FILE *stream );
/* Returns char written or EOF on error */
eg. fputc( ‘A’ , file_ptr );

int fputs (char *str, FILE *stream );
/* Returns zero value on success, non zero on error */
eg. fputs( “Hello world\n”, file_ptr);

int fprintf ( FILE *stream, char *conversion_string, arg_list);
/* Returns the number of characters printed */
eg. fprintf ( file_ptr , “%d %d %d”, &int1, &int2, &int3);

Checking if an error occurred during a read/write -

int ferror ( FILE *stream );
/* Returns zero if no error, non zero on error */
eg. if (ferror(file_ptr)) /* an error occurred */

Clear a buffer associated with a stream -

int fflush( FILE *stream );
eg. fflush(stdout); /*Clear standard output buffer*/

Closing the file after use -

fclose( FILE *stream );
eg. fclose (file_ptr);

FILE *file_ptr = NULL; /* declare a file pointer variable */

Recommended way to open a file -

if ( (file_ptr = fopen(“Filename.bin”, “rb+”)) == NULL )
{  printf(“Error opening file\n”);
}

Reading from the file -

int fread ( void *ptr, size_t size, size_t num, FILE *stream);

Example of use -

fread( &float_val, sizeof(float_val), 1, file_ptr);
/* returns number of items read from file */

Writing to the file -

int fwrite( void *ptr, size_t size, size_t num, FILE *stream);

Example of use -

fwrite( &float_val, sizeof(float_val), 1, file_ptr);
/* returns number of items written to file */

Moving the file pointer ( random access of the file) -

fseek( FILE *stream, long offset, int origin);

Where origin will be one of the following -

SEEK_SET = Start of file.
SEEK_CUR = Current position in file.
SEEK_END = End of file.

Example of use -

fseek( file_ptr, (long)-1 * sizeof(int), SEEK_CUR);

Example will move the file pointer back one int, i.e. read/write the previous integer stored in the file.

Report current file pointer position -

long ftell( FILE *stream ); /* returns -1 when an error occurs */

Reset file pointer back to the start of the file -

void rewind ( FILE *stream );
/* resets EOF and error flags in the process */

Closing the file after use -

fclose( FILE *stream );

Example of use -

fclose (file_ptr);
file_ptr = NULL;

Below are some notes I initially made to help me with pointer arithmetic, you may find these useful. Increment the pointer -

*++pn;      /* increment pn then dereference pn */
*pn++;      /* dereference pn then increment pn */

Increment the value the pointer points to -

++*pn;      /* dereference pn then increment this value */
(*pn)++;    /* dereference pn, increment this value – value of expression is pre-incremented value */

Arithmetic on the pointer -

*(pn + 1);  /* the value stored at pn + 1 */
*(pn + n);  /* the value stored at pn + n */

Arithmetic on the value the pointer points to -

*pn +1;     /* add one to the value pointed to by pn */

Precedence of operators is (right to left) -

( ) * –
-
++
+