Spectrum M3i.4830, Hardware Manual

Page: 65 / 136

Analog Inputs Setting up the inputs
(c) Spectrum GmbH 65
The following example reads out the number of available input ranges and reads and prints the minimum and maximum value of all input
ranges.
The input range is selected individually for each channel. Please note that the correct input path needs to be set
Standard Input ranges of path 0 (Buffered):
Standard Input ranges of path 1 (HF, 50 ohm terminated):
Read out of input features
Each input path has different features that can be read out to make the software more general. If you only operate one single card type in
your software it is not necessary to read out these features.
Please note that the input features are read out for the currently selected read AI path done by register SPC_READAIPATH. Please also note
that the following table shows all input features settings that are available throughout all Spectrum acquisition cards. Some of these features
are not installed on your specific hardware. The columns for the input paths show which settings are available for which input path on a
standard card:
spcm_dwGetParan_i32 (hDrv, SPC_READAIPATHCOUNT, &lNumOfPaths);
for (lPath = 0; lPath < lNumOfPaths; lPath++)
{
spcm_dwSetParan_i32 (hDrv, SPC_READAIPATH, lPath)
spcm_dwGetParam_i32 (hDrv, READIRCOUNT, &lNumberOfRanges);
for (i = 0; i < lNumberOfRanges; i++)
{
spcm_dwGetParam_i32 (hDrv, SPC_READRAN i, &lMinimumInputRage);
spcm_dwGetParam_i32 (hDrv, SPC_READRAN i, &lMaximumInputRange);
printf („Path %d Range %d: %d mV to %d mV\n“, lPath, i, lMinimumInputRange, lMaximumInputRange);
}
}
Register Value Direction Description
SPC_AMP0 30010 read/write Defines the input range of channel0.
SPC_AMP1 30110 read/write Defines the input range of channel1.
200 ± 200 mV calibrated input range for the appropriate channel.
500 ± 500 mV calibrated input range for the appropriate channel.
1000 ± 1 V calibrated input range for the appropriate channel.
2000 ± 2 V calibrated input range for the appropriate channel.
5000 ± 5 V calibrated input range for the appropriate channel.
10000 ± 10 V calibrated input range for the appropriate channel.
500 ± 500 mV calibrated input range for the appropriate channel.
1000 ± 1 V calibrated input range for the appropriate channel.
2500 ± 2.5 V calibrated input range for the appropriate channel.
5000 ± 5 V calibrated input range for the appropriate channel.
Register Value Direction Description
SPC_READAIPATH 3121 read/write Selects the input path which is used to read out the features. Please note that this settings does not
change the current path selection.
SPC_READAIFEATURES 3101 read Returns a bit map with the available features of that input path. The possible return values are listed
below.
Value Path 0 Path 1 Description
SPCM_AI_TERM 00000001h x fixed Programmable input termination available
SPCM_AI_SE 00000002h fixed fixed Input is single-ended. If available together with SPC_AI_DIFF: input type is software selectable
SPCM_AI_DIFF 00000004h Input is differential. If available together with SPC_AI_SE: input type is software selectable
SPCM_AI_OFFSPERCENT 00000008h x x Input offset programmable in per cent of input range
SPCM_AI_OFFSMV 00000010h Input offset programmable in mV
SPCM_AI_OVERRANGEDETECT 00000020h Programmable overrange detection available
SPCM_AI_DCCOUPLING 00000040h x x Input is DC coupled. If available together with AC coupling: coupling is software selectable
SPCM_AI_ACCOUPLING 00000080h x x Input is AC coupled. If available together with DC coupling: coupling is software selectable
SPCM_AI_LOWPASS 00000100h x x Input has a selectable low pass filter (bandwidth limit)
SPCM_AI_ACDC_OFFS_COMP 00000200h Input has a selectable offset compensation for HF-Path with AC/DC coupling/source missmatch.
SPCM_AI_AUTOCALOFFS 00001000h x x Input offset can be auto calibrated on the card
SPCM_AI_AUTOCALGAIN 00002000h x Input gain can be auto calibrated on the card
SPCM_AI_AUTOCALOFFSNOIN 00004000h Input offset can auto calibrated on the card if inputs are left open
SPCM_AI_INDIVPULSEWIDTH 00010000h Trigger pulsewidth is individually per channel programmable