Guralp Systems CMG-DCM - Manual (Page 125)

Operator's guide
The firmware
Reinstalling the firmware from scratch is a more involved process, and
you should only need to do it if the root or boot partitions of the DCM
become corrupted. In this case, you can use the boot loader (which is
resident in hardware) to update them. You will need a second DCM or
Linux computer attached to the console port in order to do this.
Note that the firmware is not the same as the distribution. If you want
to ensure that your DCM has all the latest software, you should use the
upgrade command described above. Reinstalling the firmware will
reset any changes you have made to the system.
The procedure for installing new firmware depends on which revision
of the DCM design you have. All recent DCM units use “MkII”
firmware. If you are unsure which hardware type you are using,
contact Güralp Systems.
MkII DCM or AM
Mark II DCMs and AMs have a 256 kb bootloader, a 1 Mb kernel image
and a 64 Mb file system image. Currently all surface DCM units are the
Mark II design.
1. Download the latest revision of the root (and boot, if
appropriate) files from the Güralp Systems website at
http://www.guralp.net/software/modules/DCM/
2. Obtain the flashdcm tool from the same site. This is a Linux
utility which enables you to access the DCM's firmware. If you
are using a second DCM, flashdcm will already be present on
it.
3. Note the baud rate of the DCM's console port (115200 by
default).
4. Power down the DCM.
5. On the second computer or DCM, issue the command
flashdcm -r root-file -b boot-file -s baud-rate -p root-
password -d port
where root-file and boot-file are the images you wish to
transmit, baud-rate is the baud rate of the DCM's console port,
root-password is the password of the user root on the DCM
( not any other administrative account), and port is the port
number of the serial interface (on the second computer or DCM)
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