Signametrics
44
Remarks
Executing
the
DMMRead
function causes the DMM to perform a single conversion and
retrieve the result. The DMM, performs all scaling and conversion required, and returns
the result as a 64-bit double-precision floating-point number in the location pointed to by
lpdResult
. It can read all the
Primary
functions (those that can be selected using
DMMSetFunction()
and
DMMSetRange()
). Returned result is a scaled value which is
normilized to the selected range. That is . That is, it returns 200 for 200mV input in the
240 mV range, and 100 for 100 k
input in the 330k
range. Alternatively use the
DMMReadNorm()
function for base units read function, or
DMMReadStr()
to return
the results as formated string of the
DMMRead()
.Very large values are indication of
over range condition.
Parameter
Type/Description
nDmm
int
Identifies the DMM. DMMs are numbered starting with zero.
lpdResult
double *
Points to the location to hold the next reading.
Return Value
The return value is one of the following constants.
Value
Meaning
DMM_OKAY
DMM initialized successfully.
Negative Value
Error code
Positive Value
Warning code, including over range.
Example
double dResults[100];
int status;
For(i=0; I < 100; i++)
DMMRead(0, &dResults[i]);// Read to a buffer
DMMReadNorm
Description
Take a reading that is in base value.
#include "SMU2060.H"
int DMMReadNorm(int
nDmm
, double *
lpdRead
)
Remarks
This function returns a double floating-point reading. Unlike
DMMRead()
the returned
value is in base units. That is, it returns 0.2 for a 200 mV input and 1e6 for a 1.0 M
.
Very large values are indication of over range condition.
Parameter
Type/Description
nDmm
int
Identifies the DMM. DMMs are numbered starting with zero.
lpdRead
double *
Pointer to a location where the reading is saved.
Return Value
Integer value version code or an error code.
Value
Meaning
DMM_E_RANGE
Over/Under range error.
Negative Value
Error code
DMM_OKAY
Valid return.
