SRS Labs SR715, Руководство пользователя

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REMOTE PROGRAMMING
4-15
TxGpib (sr720,"OUTF2"); /
*
verbose binary output
*
/
TxGpib (sr720,"STRT;
*
WAI;XALL?"); /
*
trigger a measurement, wait until it's over, then
ask for results
*
/
MakeTalk (sr720); /
*
make LCR a GPIB talker
*
/
count = 15;
rarray (&status, &length, &count, data, &seg); /
*
read output into array data[]
*
/
/
*
Check the programming section of the SR720 for
detailed information on binary return formats.
*
/
/
*
split up status byte to check for errors and measurement type
*
/
errs = data[2] & 15; /
*
mask = 0000 1111
*
/
mtype = data[2] & 48; /
*
mask = 0011 0000
*
/
mtype /= 16; /
*
now mtype = 0000 00xx
*
/
switch (errs)
{
case 0: printf ("Measurement ok (no errors).\n"); break;
case 1: printf ("? No measurement made ?\n"); break;
case 2: printf ("Measurement overloaded.\n"); break;
case 4: printf ("Underrange error.\n"); break;
case 8: printf ("Overrange error.\n"); break;
case 15: printf ("Out of range error.\n"); break;
default: break;
}
/
*
transfer major parameter bytes(4) to create a single precision FP number
*
/
memcpy (&maj, &data[3], 4); /
*
store four bytes as a floating point number
*
/
/
*
now do the same for the minor parameter.
*
/
memcpy (&min, &data[8], 4);
printf ("%s = %7.4e, %s = %7.5e.\n", mmaj[mtype], maj, mmin[mtype], min);
}
/
* ******************************************************************* *
/
void InitGpib (void) /
*
initialize the CEC GPIB card as controller
*
/
{
int my_address, system_controller;
unsigned seg;
/
*
find cec card address
*
/
for ( seg=0x4000 ; seg < 0xF000 ; seg += 0x400 )
{ if ( (peek (seg,50) == 'C') && (peek (seg,51) == 'E') && (peek (seg,52) == 'C') ) break; }
if ( pc488_seg(seg))
{ printf ( " no gpib card installed\n"); exit(0); }
my_address = 21;
system_controller = 0;
initialize (&system_controller, &my_address); /
*
init controller (CEC) function
*
/
transmit (&status, "IFC UNT UNL DCL REN"); /
*
device clear and remote enable
*
/
}
/
* ********************************************************************* *
/
void MakeTalk (int address) /
*
make device at address a talker
*
/
{