333 File System

 !!! THIS PAGE IS OUTDATED !!! PLS SEE 353_File_System

Elphel Model 333 Camera File Systems

Camera has 3 file systems, you may browse them http://<camera_ip>/admin-bin/editcgi.cgi?file=/ One of these FS use camera system memory, two others - flash.

cramfs

This is a readonly file system (compressed) that is written only when the whole flash memory is updated using flashit utility. It contains root file system, most of the system files and applications that do not need to be modified during normal camera operation.

tmpfs

This is a file system that uses a part of the system SDRAM (RAM-disk), it is fast, mounted with both read and write access but everything in it disappears when the power is disconnected.

This FS is mounted as /var, there is a simlink to /var/html so you may ftp temporary web pages there (i.e. /var/html/your_web_page.html) and they will appear as http://camera_ip/var/your_web_page.html

jffs2

This one is a camera "hard drive" - this FS can be written to and the contents will survive powering the system down. Physically it resides in the camera flash memory (biggest of the 3 partitions) so there is a limitation to the total number of writes to each block (~100,000). It is a big number for occasional writes, but if some program will write there flushing after each byte written - it will definitely kill the camera soon.

/etc is in jffs2, particularly /etc/httpd/html is the root of http server, so /etc/httpd/html/index.html is what is visible as http://<camera_ip> /usr/local is also in this file system, you may ftp there some programs you would like to try without overwriting all of the flash memory.

boot partition

The first block in the flash memory (it is rather big - 128KB) is not included in any file system and is not overwritten by the flashit utility (if "-a" switch is not included). In addition to the bootloader this sector holds multiple "key=value" pairs, most important currently is camera serial number (same as Ethernet MAC address).