AMC 68VZ328 software manual Close the file afterwards fclose filehandle

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printf (“Cannot open file\n”); exit (-1);

}

// print the string to file

fprintf (file_handle, “Hello World!\n”);

//close the file afterwards fclose (file_handle);

}

This application shows how to open and configure the RS485 serial port for communication. It will write the same hello world string to the serial port and then close and exit gracefully.

//serial.c

//This program opens the RS485 serial port, configures it to

//run

//at 9600 bps and transmits a string containing “Hello World” #include <stdio.h>

#include <fcntl.h> #include <termios.h> void main ()

{

int file_handle;

struct termios io_settings;

char hello_string[] = “Hello World”;

// open the serial port

file_handle = open (“/dev/ttyS1”, O_RDWR);

//check if an error occured if (file_handle == -1) {

printf (“Cannot open serial port\n”); exit (-1);

}

//set the serial port speed to 9600 in both directions tcgetattr (file_handle, &io_settings);

cfsetospeed (&io_settings, B9600); cfsetispeed (&io_settings, B9600);

tcsetattr (file_handle, TCSANOW, &io_settings);

//transmit the string

write (file_handle, (void *) hello_string, sizeof (hello_string) - 1);

//close the serial port when finished close (file_handle);

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Contents DimmPCITM 68VZ328 Hardware / Software Manual DimmPCITM Software Development Kit Copyright noticeContact Information NETdimm Developers Kit Quick Start Guide Etc/issue Page This page left intentionally blank Introduction Launching Linux at the embeddedPage What’s on the CD? System RequirementsThis page left intentionally blank CPU Module FeaturesUC68VZ328 Embedded Microcontroller BackplaneGeneral Description CPU Module DescriptionBackplane Description Architecture CPU ArchitectureMemory Map MCU CoreSystem Memory Memory Memory MapLayout of the Flash and Flash Schematic Layout of the Flash Sdram Ethernet Controller Viewing the Ethernet MAC IDNETdimm Ethernet Schematic Digital I/O IOdimmDigital Output Schematic Analog Output Schematic Analog Input Schematic Digital to Analog Converter Schematic Highlights RS-232Watchdog Usage LCD Schematic LCD InterfaceDimmPCITM Signal Descriptions DimmPCITM signals for System SlotPCI Electrical Characteristics Maximum RatingsThis page left intentionally blank Builder Kit Installing the dimmPCI TM SystemInstallation Before beginningConfiguring and compiling the µClinux kernel Creating a ROM image Customizing the filesystemAccessing your dimmPCI development board via the serial port Dynamic IP Accessing the NetworkStatic IP Accessing your dimmPCI development board via telnet Compiling your own source codeUsing NFS to streamline the development cycle Home directory/dimmpci/source Updating Applications on your dimmPCI module MethodThis page left intentionally blank Programming the uC68VZ328 LoaderOops Cd /opt/boottools/oops Oops -p /dev/ttyS0 -k kernel.bin Page Page This page left intentionally blank Appendix Sample CodeClose the file afterwards fclose filehandle Page Longwatchdogid #include unistd.h #include stdio.h int main void This page left intentionally blank Journalling Flash File System Umount /usr Sbin/mkjffs /dev/flash0 Page This page left intentionally blank Development Tool Chains Normal Usage of the PIC-COFFTool Chain Page This page left intentionally blank D1 Application Note IntroductionKernel and Filesystem Configuration Kernel and Filesystem Configuration Flow Chart YESAvailable Digital I/O Pins List of all available digital I/O pins Programming Structure Dimmio structure descriptionDigital I/O Functions Page Sample Programs In0 In1 In2 In3 In4 In5 In6 In7 Out0 Even ParityMknod io1 c 123 Page This page left intentionally blank D2 Application Note AbstractKernel Configuration RequirementsAgain, from the main menu under Network device support Kernel Configuration Flow Chart AtCommandPrompt Filesystem Configuration Cd /opt/filesystem name make clean Make Filesystem Configuration Flow Chart Modifications to ‘rc’ fileHost machine Configuration TestingPage This page left intentionally blank Using Multiple NETdimm Modules Application NoteSimple Server & Client Inetd based Server & ClientPage This page left intentionally blank Using Analog and Digital I/O with IOdimmCd /opt Cp -Rpdx newfs iodimmmfs ADC MAX1203 Available I/O Pins Category Channel Backplane System Backplane Header Slot PinFunctions Digital Inputs and Outputs+ Κ Iodimm/dio Samples/cardspecific/iodimm/dio Page This page left intentionally blank Using Oops Purpose & basic format of files for oopsUpload & Flash Upload & Run DownloadCommon oops program arguments Appendix This page left intentionally blank 104 Preamble Licensing, Copyrights & LiabilityDimmPCITM Software Development Kit Distribution 106 107 108 109 No Warranty Appendix How to Apply These Terms to Your New Programs111 112 113 This page left intentionally blank 114 References/ Suggested Reading