Introduction

Welcome to the fantastic and revolutionary world of embedded computing. Not really long ago, Intel 386 @ 33 MHz (1985) and Intel 486 @ 66 MHz (1989) had been the mainstream processors of desktop PCs and corporate servers for many years. Today, the 32-bit ARM-based embedded computer, low-power and small-in-size, contains much more functionalities than an average PC in 1990s had:

High reliability, industrial grade (-40 to +85 ^oC)

High speed @ 80 MHz, low power.

LAN and WAN (PPPoE) interface

USB host and client interface

Solid state disk storage (onboard and external)

Real-time clock with NTP calibration

HTTP web server

FTP server

Telnet server

DDNS (Dynamic DNS)

SNMP V1,V2,V3 SDK (MD5 / SHA Authentication, DES / AES Privacy)

Web-based firmware update.

Human interface: LCD, keypad

Rich I/O interfaces: UART, SPI, I2C, GPIO

uClinux 2.4. 100% user programmable

General Hardware Specifications

The exact hardware configuration may vary among products as well as applications. Nevertheless, the followings are common to all targets:

CPU	Winbond ARM7TDMI W90N745 / W90N710 80 MHz Little Endian
Ethernet 10/100 M	1
ROM (NOR FLASH)	4 / 8 MB
SDRAM (16-bit X 4 M)	8 /16 MB
UART 300-115200 bps	Up to 4
AC97 Play/Record	1
USB 1.1 Host	1
USB 1.1 Client	1
I2C / SPI	1
Watchdog (4.5 seconds)	1

The followings are only available on W90N710 processor.

SD/Smart Card	1
LCD controller	1
Keyboard	1

Memory

Flash ROM	1.5 MB - boot loader, uClinux, ROM file system 2.5 MB ¡V user space (for 4 MB flash) 6.5 MB ¡V user space (for 8 MB flash)
SDRAM	3 MB ¡V System 1 MB - RAM file system 1 MB - RAM image of ROM file system 3 MB¡Vuser space (for 8 MB SDRAM) 10 MB ¡V user space (for 16 MB SDRAM)

Disk Storage

Internal	JFFS2	2.5 MB (for 4 MB flash) 6.5 MB (for 8 MB flash)
Internal	RAM FS	1 MB¡VRAM file system
External	VFAT	USB disk¡Vtypical 1 GB¡V32 GB
External	VFAT	SD/SDHC disk¡Vtypical 1 GB¡V32 GB

File System Structure

The file system of Linux starts from the root '/', which is read-only, located in the 1 MB ROM file system. Under the root, the directories on the device are:

/bin	RO	system executable files
/dev	RO	device driver entries
/etc	RO	system settings
/proc	RO	system statistics
/usr	RW	user RAM file
/swap	RW	system temporary RAM file
/var	RW	system temporary RAM file
/tmp	RW	system temporary RAM file
/flash	RW	2.5 ¡V 6.5 MB disk space on flash (jffs2 file system)
/usb	RW	reserved for mounting USB disk
/sd	RW	reserved for mounting SD card

* RO=Read Only. RW=Read / Write

/proc Virtual File

The files in /proc directory are virtual files which contain information of the system, drivers, peripherals, etc... They are read only and can be read by console command 'cat' or viewed by browsers through FTP server.

Software Packages

ARM Tools. (GPL License)

arm-elf-gcc 3.0 is included in our distribution CD. Use the script 'install.sh' and file 'arm_tools.tar.gz' to install the tools. The tools need to run in Linux environment.

uClinux Packages. (GPL License)

The source codes of uClinux packages are located in the 'uClinux-dist/user' directory in the file 'uClinux-dist.tar.gz' of our distribution CD. These packages are only a selected subset of original uClinux distribution. If you need the full package, you can get it from http://www.uclinux.org.

The quality of these packages spread with great variance. Only some are really useful. We put these software into 3 categories:

1. System

Binaries in /bin have been pre-built by us. Users can use these binaries directly without the need of building them from source code.

inetd - Internet service server

boa - HTTP server

ftpd - FTP server

telnetd - Telnet server

login - Telnet login

ifconfig - network configuration utility

route - network route utility

dhcpc - DHCP client

sh - command shell

ping - ping utility

2. Application Specific

Users need to customize these source code by themselves.

openssl - secure communication

smtpclient - email client

mail - email client

snmpd - SNMP agent

samba - samba server

3. Reference Only

The complete list of uClinux-dist/user:

a60 agetty at bash boa boottools bpalogin br2684ctl brcfg bridge-utils cal cgi_generic cksum clock COPYING COPYING.LIB cpu cramfs cron demo dhcpcd dhcpcd-new dhcpd dhcp-isc dhrystone diald discard DISTRIBUTION dnsmasq e2fsprogs elvis-tiny ethattach

ez-ipupdate fdisk fileutils flash flashw flatfsd freeswan frob-led fs fswcert ftpd games gdbserver gdsd gettyd hd httpd hwclock ifattach include inetd init init.org ipchains ipfwadm ipmasqadm ipportfw ipredir iproute2 iptables jffs-tools klaxon

l2tpd lcd ledcon levee libz.a lilo lirc lissa loattach login Makefile mathtest mawk mbus mini_httpd mount msntp mtd-utils musicbox netflash netstat-nat net-tools null nwsh oggplay openssl palmbot pciutils pcmcia-cs perl ping pktdelay

play playrt plug portmap pppd pppd.small pptp-client pptpd procps python rdate readprofile recover reiserfsprogs rootloader route routed rp-pppoe rtc-ds1302 rtc-m41t11 samba sash sethdlc setserial sh shutils slattach smbmount smtpclient snmpd squid ssh

stp strace stty stunnel sysutils tcpblast tcpdump tcpwrappers tcsh telnet tftp tftpd threaddemos thttpd tinylogin tip tpt traceroute tripwire ucdsnmp version vixie-cron vplay vpnled w3cam wget wireless_tools zebra

Development Packages. (Commercial License)

The following software packages are supplied by us, under commercial license, not GPL license. They are designed for customers who use our hardware products or are our design licensees. As long as the software is running on our hardware, users may use and modify the software freely without further obligations.

Binary & Source Code

These source codes come from real products in production quality, not just amateur demonstrations. They can be used as design templates for developing custom products, especially for users who have no or little uClinux experiences.

cgi	CGI program for web-based applications
lib	Commonly used APIs for building programs
etmd	Service for UDP-based IP address locator. Working together with 'Etm.exe' utility on Windows.
siod	Full-featured TCP/UDP to serial converter
www/sys	Html pages with JavaScript for web-based applications
www/demo	web interface demo
example	program examples
cgidemo	cgi examples

Binary Code

These software are driver-level programs which are very hardware dependent and greatly affect the system stability. Moreover, there's no need for users to customize these components. In order to maintain the system quality, only binary forms are provided.

sys_service	System service (FLASH programming, triggering watchdog, system initialization, etc ¡K)
cgisys	CGI interface to sys_service

Technical Support Policy

uClinux Packages & ARM Tools. (GPL License)

The uClinux distribution under GPL license contains millions of line of program source. To give an answer to a simple question like "Why my uClinux build becomes unstable ?", may need probably hundreds of hours for us to find out what's wrong there. There's no way we can afford to provide this kind of technical support. Like it or not, it¡¦s the very truth of GPL software : NO COST, NO WARRANTY, NO SUPPORT. Need assistance ? Try Google.

Therefore, our technical support for uClinux covers only the binaries that we built.

uClinux-2.4x	(linux.zip) pre-built binary
/user	(inetd, boa, ftpd, telnetd, login, ifconfig, route, dhcpc, sh, ping, ping) pre-built binary

All source codes in the uClinux distribution are NO SUPPORT.

Development Packages. (Commercial License)

Both binary and source of these software packages are fully supported.