Signametrics Corporation SMU2060, Руководство оператора

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Signametrics
Negative Value Error code
Positive Value < 100 The length of the returned string
Postive Value ≥ 100
Warning code
Example
char cBuf[64];
int length = DMMErrString( -3, cBuf, 48);
DMMFrequencyStr
SMU2060  SMU2064 
Description
Return the next DMM frequency reading, formatted for printing.
#include "SMU2060.h"
int DMMFrequencyStr ( int
nDmm,
LPSTR
lpszReading
)
Remarks
This function makes frequency measurement and returns the result as a string formatted
for printing. The print format is fixed to six digits plus units, e.g., 05.001 Hz. If the
DMM is in Autorange, be certain to take an amplitude reading before using this
command. It may take several calls to
DMMFrequencyStr() to get the measured
frequency, because the DMM frequency counter uses a frequency ranging scheme which
gets activated only when a frequency or period reading function is received. If the
previously measured frequency was 2 Hz and the frequency being measured is 300 kHz
(or vise versa), it might take as many as six calls to
DMMFrequencyStr() or any of the
other frequency measurement functions, to read the correct frequency. To improve this
use the
DMMSetCounterRng() is function requires the DMM to be in either VAC or
IAC function and at the appropriate range.
Parameter Type/Description
nDmm
int Identifies the DMM. DMMs are numbered starting with zero.
lpszReading
LPSTR Points to a buffer (at least 64 characters long) to hold the
converted result.
Return Value
The return value is one of the following constants.
Value Meaning
Negative Value
Error code
Positive Value < 100 The length of the returned string
Postive Value ≥ 100 Warning code
Example
char cBuf[64];
int status;
status = DMMFrequencyStr(0, cBuf);
DMMGetACCapsR
SMU2060  SMU2064 