Moxa Technologies user manual EM-1240-LX FAQ

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EM-1240-LX FAQ

FAQ 1 Why can I only use vfork( ),and am unable to use fork( )?

Answer 1 uClinux only supports vfork( ). It does not support fork( ). Note that when using vfork( ), the parent process will hang until the child process calls an exec group API, or exits.

FAQ 2 When using a pthread group API, why cannot I use SIGUSR1 and SIGUSR2?

Answer 2 Since a pthread group API uses SIGUSR1 and SIGUSR2 to do a pthread control suspend, restart exit function, we cannot use the SIGUSR1 and SIGUSR2 signals. You will get the same result if you link the pthread. This means that you cannot use -1pthreadto add an option to the linker.

FAQ 3 What is the correct format for linking to an API?

Answer 3 arm-elf-gcc –W1, -elf2flt

(In this example, the API converts elf format to flat format.)

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Contents EM-1240-LX User’s Manual First Edition, NovemberCopyright Notice Table of Contents Chapter EM-1240-LX Device API Introduction Package Checklist Product FeaturesOverview EM-1240-LXProduct Specifications Hardware SpecificationsSoftware Specifications Hardware Block Diagram Appearance EM-1240 Development Kit Embedded ModuleEM-1240 Embedded Module EM-1240 Development Kit Dimensions Installing the EM-1240-LX LED IndicatorsWiring Requirements Connecting Data Transmission Cables Connecting the PowerGrounding the EM-1240-LX Connecting to the Network Connecting to a Serial DeviceReset Button Internal SD SocketAdditional Functions Serial Console PortReal-time Clock Getting Started Powering on the EM-1240-LX Connecting the EM-1240-LX to a PCConsole Port Default IP Address Default Netmask Telnet192.168.3.127 255.255.255.0 192.168.4.127 255.255.255.0Configuring the Ethernet Interface Ifconfig eth0 Dhcpcd -p -a eth0 & dhcpcd -p -a eth1Installing a Secure Digital SD Memory Card Installing the EM-1240-LX Tool Chain Developing Your ApplicationsStep #mount -t iso9660 /dev/cdrom /mnt/cdromEM-1240-LX User’s Manual Compiling Hello.c PATH=/usr/local/arm-elf/bin$PATHUploading Hello to the EM-1240-LX #makeRunning Hello on the EM-1240-LX # chmod 755 hello #./helloMake File Example Code Cflags =Software Package EM-1240-LX Software Architecture Flash Context Flash Address Size Access control Journaling Flash File System JFFS2Additional information about JFFS2 is available at EM-1240-LX Software Package Bin DevPtyp0 Ppp Pio Rtc Ram1 Ram0 Null Kmem Mem Cua0 Console Tty Configuring the EM-1240-LX ‰ Iptables ‰ NATExample default enable Enabling and Disabling DaemonsDefault Home Page address Adding a WebLocal Host Packets Define policy rules, and Append or delete rules UsageExamples Define policy for chain rules Enabling NAT at Bootup NAT ExampleConfiguring Dial-in/Dial-out Service Configuring PPPoEDial-out Service Dial-in ServiceHow to Mount a Remote NFS Server Dynamic Driver Module Load/UnloadRamdiskupkernel em1240-1.x.bin /ramdiskreboot Upgrading the KernelUpramdisk Cd ramdiskUpgrading the Root File System & User Directory Upramdisk Cd ramdiskUser Directory Backup-EM-1240-LX to PC Ramdiskbackupfs /ramdisk/usrdisk-backupLoading Factory Defaults Mirroring the Application Program and ConfigurationAutostarting User Applications on Bootup Checking the Kernel and Root File System VersionsFsversion Cat /etc/versionEM-1240-LX Device API RTC Real-time Clock BuzzerUart Interface UC Finder Windows UC Finder EM-1240-LX User’s Manual UC Finder EM-1240-LX User’s Manual UC Finder Linux UC Finder System Commands Busybox µClinux normal command utility collectionFile manager EditorNetwork ProcessOther Moxa Special UtilitiesSnmp Agent with MIB II & RS-232 Like Group Snmp Agent with MIB II & RS-232 Like Group Ip MIB Tcp MIB Udp MIBSnmp MIB RFC1317 RS-232 like group supported variables Rs232 MIBEM-1240-LX FAQ Service Information Moxa Internet Services Following services are providedProblem Report Form Moxa Product † EM-1240-LX Serial NumberProduct Return Procedure