Reset to default via SD Card interface

If a SD card slot is available, the "autorun.txt" ( example) file can be used to perform a reset to default:

• Create a text file on a SD card called "autorun.txt". Enter the line "restart clear" ( more) followed by a 'enter' into this file.
• Place the SD card into the slot and turn on the product. The command in the autorun.txt file is executed. Note: this is an endless loop - the command resets the product, which causes the product to restart and execute the command again. There is no harm caused by that.
• Rather than using the 'restart clear' command, other configuraiton commands can be used to only modify those settings in questions.  more
• Turn off the product after 10 seconds. Delete the "autorun.txt" file.

The product is now in default state.