Agilent Technologies E8663B, N5183A, N5181A/82A Sockets LAN Programming and C, Sockets on Unix

Programming Examples

LAN Programming Interface Examples

status = viWrite(instr, (ViBuf)"*IDN?\n", 6, &retCount);

//Read the sig gen response

status = viRead(instr, (ViBuf)buffer, MAX_COUNT, &retCount);

buffer[retCount]= '\0';	// Indicate the			end	of the string
printf("Signal Generator ID = ");	// Print header			for	ID
printf(buffer);	//	Print	the ID	string
printf("\n");	//	Print	carriage return

//Flush the read buffer

//Set sig gen power to -5dbm

status = viWrite(instr, (ViBuf)"POW:AMPL -5dbm\n", 15, &retCount);

//Query the power level

status = viWrite(instr, (ViBuf)"POW?\n",5,&retCount);

//Read the power level

status = viRead(instr, (ViBuf)buffer, MAX_COUNT, &retCount);

buffer[retCount]= '\0';	// Indicate the end of the string
printf("Power level = ");	// Print header to the screen
printf(buffer);	// Print the queried power level
printf("\n");
status = viClose(instr);	// Close down the system
status = viClose(defaultRM);
return 0;
}

Sockets LAN Programming and C

The program listing shown in “Queries for Lan Using Sockets” on page 107 consists of two files; lanio.c and getopt.c. The lanio.c file has two main functions; int main() and an int main1().

The int main() function allows communication with the signal generator interactively from the command line. The program reads the signal generator's hostname from the command line, followed by the SCPI command. It then opens a socket to the signal generator, using port 5025, and sends the command. If the command appears to be a query, the program queries the signal generator for a response, and prints the response.

The int main1(), after renaming to int main(), will output a sequence of commands to the signal generator. You can use the format as a template and then add your own code.

This program is available on the signal generator Documentation CD- ROM as lanio.c.

Sockets on UNIX

In UNIX, LAN communication via sockets is very similar to reading or writing a file. The only difference is the openSocket() routine, which uses a few network library routines to create the TCP/IP network connection. Once this connection is created, the standard fread() and fwrite() routines are used for network communication. The following steps outline the process:

1. Copy the lanio.c and getopt.c files to your home UNIX directory. For example, /users/mydir/.

Agilent N518xA, E8663B, E44x8C, and E82x7D Signal Generators Programming Guide 105