Moxa Technologies UC-7400-LX Plus User manual

UC-7400-LX Plus User’s Manual
Sixth Edition, December 2010
www.moxa.com/product
2010 Moxa Inc. All rights reserved.
Reproduction without permission is prohibited.

UC-7400-LX Plus User’s Manual
The software described in this manual is furnished under a license agreement and may be used only in
accordance with the terms of that agreement.
Copyright Notice
Copyright 2010 Moxa Inc.
All rights reserved.
Reproduction without permission is prohibited.
Trademarks
MOXA is a registered trademark of Moxa Inc.
All other trademarks or registered marks in this manual belong to their respective manufacturers.
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Information in this document is subject to change without notice and does not represent a commitment on the
part of Moxa.
Moxa provides this document “as is,” without warranty of any kind, either expressed or implied, including, but
not limited to, its particular purpose. Moxa reserves the right to make improvements and/or changes to this
manual, or to the products and/or the programs described in this manual, at any time.
Information provided in this manual is intended to be accurate and reliable. However, Moxa assumes no
responsibility for its use, or for any infringements on the rights of third parties that may result from its use.
This product might include unintentional technical or typographical errors. Changes are periodically made to the
information herein to correct such errors, and these changes are incorporated into new editions of the
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Table of Contents
Chapter 1 Introduction..................................................................................................1-1
Overview.................................................................................................................................. 1-2
Software Architecture .............................................................................................................. 1-2
Journaling Flash File System (JFFS2).......................................................................... 1-3
Software Package ......................................................................................................... 1-4
Chapter 2 Getting Started.............................................................................................2-1
Powering on the UC-7400-LX Plus......................................................................................... 2-2
Connecting the UC-7400-LX Plus to a PC .............................................................................. 2-2
Serial Console............................................................................................................... 2-2
Telnet Console.............................................................................................................. 2-3
SSH Console................................................................................................................. 2-4
Configuring the Ethernet Interface .......................................................................................... 2-5
Modifying Network Settings with the Serial Console.................................................. 2-5
Modifying Network Settings over the Network............................................................ 2-6
Using IPv6 Command Utilities..................................................................................... 2-6
Configuring the WLAN through the PCMCIA Interface ............................................. 2-8
Connecting to 3G Networks through the PCMCIA Interface..................................... 2-14
Test Program—Developing Hello.c....................................................................................... 2-16
Installing the Tool Chain (Linux)............................................................................... 2-16
Checking the Flash Memory Space............................................................................ 2-17
Compiling Hello.c ...................................................................................................... 2-17
Uploading and Running the “Hello” Program............................................................ 2-18
Developing Your First Application ........................................................................................ 2-18
Testing Environment .................................................................................................. 2-18
Compiling tcps2.c....................................................................................................... 2-19
Uploading and Running the “tcps2-release” Program................................................ 2-20
Testing Procedure Summary....................................................................................... 2-22
Chapter 3 Managing Embedded Linux ........................................................................3-1
System Version Information..................................................................................................... 3-2
System Image Backup.............................................................................................................. 3-2
Upgrading the Firmware............................................................................................... 3-2
Loading Factory Defaults............................................................................................. 3-5
Enabling and Disabling Daemons............................................................................................ 3-5
Starting a ProgramAutomatically at Run-Level...................................................................... 3-8
Adjusting the System Time...................................................................................................... 3-9
Setting the Time Manually ........................................................................................... 3-9
Write current system time to RTC................................................................................ 3-9
NTP Client.................................................................................................................. 3-10
Updating the Time Automatically .............................................................................. 3-10
Cron—Daemon for Executing Scheduled Commands............................................................3-11
Connecting Peripherals..........................................................................................................3-12
USB Mass Storage...................................................................................................... 3-12
CF Mass Storage......................................................................................................... 3-12
Chapter 4 Managing Communications........................................................................4-1
Telnet / FTP ............................................................................................................................. 4-2
DNS ......................................................................................................................................... 4-2

Web Service—Apache............................................................................................................. 4-3
IPTABLES............................................................................................................................... 4-4
NAT.......................................................................................................................................... 4-8
NAT Example............................................................................................................... 4-9
Enabling NAT at Bootup.............................................................................................. 4-9
Dial-up Service—PPP............................................................................................................ 4-10
PPPoE.................................................................................................................................... 4-13
NFS (Network File System)................................................................................................... 4-15
Setting up the UC-7400-LX Plus as an NFS Server................................................... 4-15
Setting up the UC-7400-LX Plus as an NFS Client.................................................... 4-17
Mail........................................................................................................................................ 4-17
SNMP .................................................................................................................................... 4-18
OpenVPN............................................................................................................................... 4-19
IPv6 to IPv4 Tunneling..........................................................................................................4-26
Chapter 5 Programmer’s Guide....................................................................................5-1
Before Programming Your Embedded System ........................................................................ 5-2
Caution When Using File Systems............................................................................... 5-2
Using RAM File System Instead of Flash File System ................................................ 5-2
Flash Memory Map.................................................................................................................. 5-2
Linux Tool Chain Introduction................................................................................................. 5-3
Debugging with GDB..............................................................................................................5-4
Device API............................................................................................................................... 5-5
RTC (Real-time Clock)............................................................................................................ 5-5
Buzzer...................................................................................................................................... 5-5
WDT (Watch dog Timer)......................................................................................................... 5-6
UART....................................................................................................................................... 5-9
LCM........................................................................................................................................5-11
KeyPad....................................................................................................................................5-11
Make File Example................................................................................................................ 5-12
Chapter 6 Software Lock...............................................................................................6-1
Appendix A System Commands.....................................................................................A-1
Linux normal command utility collection............................................................................... A-1
System ......................................................................................................................... A-1
File Manager................................................................................................................ A-1
Editor........................................................................................................................... A-2
Network....................................................................................................................... A-2
Process.........................................................................................................................A-2
Other............................................................................................................................ A-3
Moxa Special Utilities ................................................................................................. A-3

1
1
Chapter 1 Introduction
The Moxa UC-7400-LX Plus series of RISC-based commnication platforms are ideal for your
embedded applications.All models come with 8 RS-232/422/485 serial ports, dual 10/100 Mbps
Ethernet ports, a PCMCIA interface for wireless LAN communication, and CompactFlash and
USB ports for mass storage for disk expansion.
The following topics are covered in this chapter:
Overview
Software Architecture
Journaling Flash File System (JFFS2)
Software Package

UC-7400-LX Plus User’s Manual Introduction
1-2
Overview
The UC-7400-LX Plus series of RISC-based communication platforms are ideal for embedded
applications. Features include 8 RS-232/422/485 serial ports, dual 10/100 Mbps Ethernet ports, a
PCMCIA interface for wireless LAN communication, and CompactFlash and USB ports for mass
storage disk expansion.
The UC-7400-LX Plus uses an Intel XScale IXP425 533 Mhz RISC CPU. Unlike the X86 CPU,
which uses a CISC design, the IXP425’s RISC design architecture and modern semiconductor
technology provide the UC-7400-LX Plus with a powerful computing engine and communication
functions, but without generating a lot of heat. The built-in 32 MB NOR Flash ROM and 128 MB
SDRAM give you enough memory to put your application software directly on UC-7400-LX Plus.
In addition, since the dual-LAN ports are built right into the IXP425 CPU, the UC-7400-LX Plus
is an ideal communication platform for network security applications. If your application requires
placing the UC-7400-LX Plus in a location that is not near an Ethernet LAN connection, you can
use the UC-7400-LX Plus’s PCMCIA port to attach a wireless LAN card.
The pre-installed Linux operating system provides an open software operating system for your
software program development. Software written for desktop PCs can be easily ported to the
UC-7400-LX Plus platform with a GNU cross compiler, without needing to modify the source
code. All of the necessary device drivers, such as a PCMCIAwireless LAN module and keypad,
LCM, and buzzer control, are also included with the UC-7400-LX Plus. The operating system,
device drivers, and the software you develop for your own application, can all be stored in the
UC-7400-LX Plus’s Flash memory.
Software Architecture
The Linux operating system that is pre-installed in the UC-7400-LX Plus follows the standard
Linux architecture, making it easy to port programs that follow the POSIX standard to the
UC-7400-LX Plus. Porting is done with the GNU Tool Chain provided by Moxa. In addition to the
Standard POSIXAPI, device drivers for the buzzer and CompactFlash mass storage, UART, digital
input, digital output, and wireless LAN PCMCIA card are also included in the UC-7400-LX Plus
Linux system.
AP
API
Protocol
Stack
Device
Driver
Microkernel
User Application Daemon (Apache, Telnet, FTPD, SNMP)
Application Interface (POSIX, Socket, Secure Socket)
TCP, IP, UDP, CMP, ARP, HTTP, SNMP, SMTP
PCMCIA, CF, WLAN, USB, UART, RTC, LCM, Keypad
Memory control, Schedule, Process
RS-232/422/485, Ethernet, PCMCIA, CompactFlash, USB
File
System
Hardware
lenreKSO

UC-7400-LX Plus User’s Manual Introduction
1-3
The UC-7400-LX Plus’s built-in Flash ROM is partitioned into Boot Loader, Linux Kernel, Root
File System, and User Root File System partitions.
In order to prevent user applications from crashing the Root File System, the UC-7400-LX Plus
uses a specially designed Root File System with protected configuration for emergency use. This
Root File System comes with serial and Ethernet communication capability for users to load the
Factory Default Image file. The user directory saves the user’s settings and applications.
To improve system reliability, the UC-7400-LX Plus has a built-in mechanism that prevents the
system from crashing. When the Linux kernel boots up, the kernel will mount the root file system
for read only, and then enable services and daemons. During this time, the kernel will start
searching for system configuration parameters via rc or inittab.
Normally, the kernel uses the Root File System to boot up the system. Since the Root File System
is protected and cannot be changed by the user, this provides a “safe” zone.
For more information about the memory map and programming, refer to Chapter 5,
“Programmer’s Guide.”
Journaling Flash File System (JFFS2)
The User Root File System in the flash memory is formatted with the Journaling Flash File
System (JFFS2). The formatting process places a compressed file system in the flash memory,
transparent to the user.
The Journaling Flash File System (JFFS2), which was developed byAxis Communications in
Sweden, puts a file system directly on the flash, instead of emulating a block device. It is designed
for use on flash-ROM chips and recognizes the special write requirements of a flash-ROM chip.
JFFS2 implements wear-leveling to extend the life of the flash disk, and stores the flash directory
structure in the RAM. A log-structured file system is maintained at all times. The system is always
consistent, even if it encounters crashes or improper power-downs, and does not require fsck (file
system check) on boot-up.
JFFS2 is the newest version of JFFS. It provides improved wear-leveling and garbage-collection
performance, improved RAM footprint and response to system-memory pressure, improved
concurrency and support for suspending flash erases; marking of bad sectors with continued use of
the remaining good sectors (which enhances the write-life of the devices), native data compression
inside the file system design, and support for hard links.
The key features of JFFS2 are:
Targets the Flash ROM directly
Robustness
Consistency across power failures
No integrity scan (fsck) is required at boot time after normal or abnormal shutdown
Explicit wear leveling
Transparent compression
Although JFFS2 is a journaling file system, this does not preclude the loss of data. The file system
will remain in a consistent state across power failures and will always be mountable. However, if
the board is powered down during a write then the incomplete write will be rolled back on the next
boot, but writes that have already been completed will not be affected.
Additional information about JFFS2 is available at:
http://sources.redhat.com/jffs2/jffs2.pdf
http://developer.axis.com/software/jffs/
http://www.linux-mtd.infradead.org/

UC-7400-LX Plus User’s Manual Introduction
1-4
Software Package
Boot Loader Redboot (v1.92)
Kernel Monta Vista embedded Linux 2.6.10
Protocol Stacks ARP, PPP, CHAP, PAP, IPv4, ICMP, TCP, UDP, DHCP, FTP, SNMP V1,
HTTP, NTP, NFS, SMTP, SSH 1.0/2.0, SSL, Telnet, PPPoE, OpenVPN
File System JFFS2, NFS, Ext2, Ext3, VFAT/FAT
OS shell command bash
Busybox Linux normal command utility collection
Utilities
tinylogin login and user manager utility
telnet telnet client program
ftp FTP client program
smtpclient email utility
scp Secure file transfer Client Program
Daemons
pppd dial in/out over serial port daemon
snmpd snmpd agent daemon
telnetd telnet server daemon
inetd TCP server manager program
ftpd ftp server daemon
apache web server daemon
sshd secure shell server
nfs-user-server network file system server
openvpn virtual private network
openssl open SSL
Linux Tool Chain
Gcc (V3.4.3) C/C++ PC Cross Compiler
GDB (V6.3) Source Level Debug Server
Glibc (V2.2.5) POSIX standard C library

2
2
Chapter 2 Getting Started
In this chapter, we explain how to connect the UC-7400-LX Plus, turn on the power, and then get
started using the programming and other functions.
The following topics are covered in this chapter:
Powering on the UC-7400-LX Plus
Connecting the UC-7400-LX Plus to a PC
Serial Console
Telnet Console
SSH Console
Configuring the Ethernet Interface
Modifying Network Settings with the Serial Console
Modifying Network Settings over the Network
Using IPv6 Command Utilities
Configuring the WLAN through the PCMCIA Interface
Connecting to 3G Networks through the PCMCIA Interface
Test Program—Developing Hello.c
Installing the Tool Chain (Linux)
Checking the Flash Memory Space
Compiling Hello.c
Uploading and Running the “Hello” Program
Developing Your First Application
Testing Environment
Compiling tcps2.c
Uploading and Running the “tcps2-release” Program
Testing Procedure Summary

UC-7400-LX Plus User’s Manual Getting Started
2-2
Powering on the UC-7400-LX Plus
Connect the SG wire to the Shielded Contact located in the upper left corner of the UC-7400-LX
Plus, and then power on the computer by connecting it to the power adaptor. It takes about 30 to
60 seconds for the system to boot up. Once the system is ready, the Ready LED will light up, and
the model name of the computer will appear on the LCM display.
NOTE After connecting the UC-7400 LX Plus to the power supply, it will take about 30 to 60 seconds for
the operating system to boot up. The green Ready LED will not turn on until the operating system
is ready.
Connecting the UC-7400-LX Plus to a PC
There are two ways to connect the UC-7400-LX Plus to a PC: (1) Through the serial console port,
and (2) via Telnet over the network.
Serial Console
The serial console port gives users a convenient way of connecting to the UC-7400-LX Plus
console utility. This method is particularly useful when using the computer for the first time. The
signal is transmitted over a direct serial connection, so that you do not need to know any of the IP
addresses in order to connect to the serial console utility.
Use the serial console port settings shown below.
Baudrate 115200 b
p
s
Parit
y
N
one
Data bits 8
Sto
p
bits: 1
Flow Control
N
one
Terminal VT100
Once the connection is established, the following window will open.
To log in, type the Login name and password as requested. The default values are both root:
Login: root
Password: root