Difference between revisions of "Using camogm with Elphel393 camera"

Revision as of 10:33, 31 May 2016

Elphel 393 series cameras can be equipped with m.2 SSD drive used for images and video recording. The camera equipped with a drive should be configured in a way that the drive can be accessible from Linux operating system. This is normally done with a configuration script which is executed during system boot. The script is usually located in the root directory on microSD card and called init_elphel393.sh. These is a set of parameters in the beginning of the script and one of them is responsible for SATA controller configuration and driver loading:

SATA_EN=1

Make sure this parameter is set to 1 if your camera is equipped with SSD drive. You should see the following messages in system log after successful initialization and auto-mounting:

[   30.587212] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
[   30.594510] ata1.00: ATA-9: SanDisk SD8SMAT128G1122, Z2320000, max UDMA/133
[   30.601426] ata1.00: 250069680 sectors, multi 1: LBA48 NCQ (depth 0/32)
[   30.616091] ata1.00: configured for UDMA/133
[   30.620669] scsi 0:0:0:0: Direct-Access     ATA      SanDisk SD8SMAT1 0000 PQ: 0 ANSI: 5
[   30.629879] sd 0:0:0:0: Attached scsi generic sg0 type 0
[   30.630011] sd 0:0:0:0: [sda] 250069680 512-byte logical blocks: (128 GB/119 GiB)
[   30.630987] sd 0:0:0:0: [sda] Write Protect is off
[   30.631106] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[   30.637003]  sda: sda1 sda2
[   30.646115] sd 0:0:0:0: [sda] Attached SCSI disk

The disk model and the number of partitions(sda1 and sda2) in the example above correspond to a test platform and they may not be the same in your camera. /dev/sda2 in this example is not partitioned and not mounted:

~# mount
/dev/root on / type ext4 (rw,relatime,data=ordered)
devtmpfs on /dev type devtmpfs (rw,relatime,size=449540k,nr_inodes=112385,mode=755)
proc on /proc type proc (rw,relatime)
sysfs on /sys type sysfs (rw,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,relatime)
tmpfs on /run type tmpfs (rw,nosuid,nodev,mode=755)
tmpfs on /var/volatile type tmpfs (rw,relatime)
devpts on /dev/pts type devpts (rw,relatime,gid=5,mode=620)
/dev/mmcblk0p1 on /mnt/mmc type vfat (rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
/dev/sda1 on /mnt/sda1 type ext2 (rw,relatime,errors=continue)

The program for video/images recording is called camogm. Its full description for previous series of Elphel cameras is available on Camogm wiki page. Current version of the program supports four sensor channels and has the same command set as the previous version, but commands can be sent to each channel separately. The program can be started the same way as described in Starting camogm section, but now it will create four command pipes instead of one and each pipe will have channel number appended to the name provided on command line:

~# ls -l /var/volatile/
prwxr-xr-x    1 root     root             0 May 31 16:55 camogm_cmd0
prwxr-xr-x    1 root     root             0 May 31 16:55 camogm_cmd1
prwxr-xr-x    1 root     root             0 May 31 16:55 camogm_cmd2
prwxr-xr-x    1 root     root             0 May 31 16:55 camogm_cmd3
drwxr-xr-x    2 root     root           180 May 31 16:54 log
drwxrwxrwt    2 root     root           160 May 31 16:54 tmp

camogm is started from init_elphel393.sh script by default and its output is may not be visible on your console. You can stop current instances of the program and restart it from you terminal if the output should be visible:

~# for i in `seq 0 3`; do echo "exit" > /var/volatile/camogm_cmd$i; done
~# camogm /var/volatile/camogm_cmd

Alternatively, the status information output can be redirected to a file as described in Sending commands to camogm.