TS-7400/TS-9441 MANUAL
SOFTWARE
/dev/mtdblock/4 - 4th MBR partition (unused in default load)
Note that the MBR installed by default on the TS-7400 contains a 443 byte bootloader
program that loads the initial power-on kernel and initrd from the first and second
partitions. Replacing it with a MBR found on a PC would not work as a PC MBR
contains an x86 code bootup program. Doing so would cause the device to constantly
reset itself every 8 seconds as the hardware watchdog expires.
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Linux uses a NAND flash filesystem called YAFFS2 for general purpose file storage.
This filesystem is a log-structured filesystem which is safe against corruption caused by
system crashes and power loss without the need for consistency checking on next
boot. A normal PC cannot use this filesystem as it is specifically designed for NAND
flash which a PC does not have.
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The TS version of Linux uses a special device driver at /dev/misc/bootloader to
accommodate the hooks needed by the "bootload" program to allow Linux to act as a
bootloader and boot other Linux kernels and operating systems.
3.8 Debian Linux OS
The typical way of doing Linux development on the TS-7400 is actually on the board itself.
Since the TS-7400 CPU is a PC-class processor in everything but power consumption
and performance, it has no problem running real PC-class operating systems such as
Linux. By running the full version of Linux (and not scaled-down microcontroller project
OS's such as ucLinux), the TS-7400 can run the entire suite of applications contained in
the Debian Linux distribution including the compilers. Since almost every open source
program available for Linux is contained within the Debian Linux binary distribution, one
rarely has to compile the large code-bases that would otherwise have forced integrators to
a complicated cross-compilation environment due to the limited RAM/Mhz of the
embedded computer. All too often, open-source projects do not anticipate the possibility
of cross-compilation in their build systems, leaving issues for the system integrator to
resolve.
The default SD card contains compilers and everything needed for developing
applications in C, C++, PERL, PHP, and SH. Java, BASIC, TCL, Python and others are
available for Debian, but not installed by default.
One can still use cross-compilers hosted on just about any platform if there is a specific
need. Technologic systems includes binary versions of the popular Linux "crosstool"
project at http://www.kegel.com/crosstool/ to allow cross-compiling on Windows/cygwin or
a Linux/i386 PC on our website website.
apt-get
When using the Debian Linux file system, adding new packages and removing undesired
ones is done all through Debian's package management. “apt“, “dpkg“, all behave as
expected. With Debian, one can easily install and remove software packages. For a quick
demonstration of how easy it is to remove and install programs with Debian, try the
following commands:
apt-get install hexedit
hexedit /etc/passwd
^C (hit CTRL+C to safely exit)
apt-get remove hexedit
apt-get install installs a package name, while apt-get remove removes the named
package. Visit the Debian home-page
for further information, since a full in-depth
discussion on Debian is outside the scope of this document.
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http://www.debian.org
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