[SENSe:]DIGital:MEMory:SAMPle:COUNt
Syntax
[SENSe:]DIGital:MEMory:SAMPle:COUNt {<count>|MIN|MAX|DEF|INFinity}, (@<ch_list>)
[SENSe:]DIGital:MEMory:SAMPle:COUNt? [{MIN|MAX},] (@<ch_list>)
Description
This command sets the number of samples to capture for buffered (memory) input operations on the 34950A Digital I/O Module. The specified sample count can be set at any time, but it will not take effect until the next time you enable memory (see [SENSe:]DIGital:MEMory:ENABle command). The width of the first channel in each bank (i.e., channels 101 and 201) controls the width of the memory operations (64K x 8 Bits, 64K x 16 Bits, or 32K x 32 Bits). The first channel on the specified bank must be configured as an input prior to starting a buffered read (see CONFigure:DIGital command).
Used With:
34950A Digital I/O Module
Parameters
|
Name |
Type |
Range of Values |
Default Value |
|
<count> |
Numeric |
Desired sample count between 1 and 65535 (for 8- and 16-bit widths) or 32767 (for 32-bit widths). MIN = 1, MAX = 65535 (32767 for 32-bit widths), INF = continuous |
0 (continuous) |
|
<ch_list> |
Numeric |
The first channel on a bank in the form (@sccc).
|
This is a required parameter |
Remarks
Depending on the width specified (see CONFigure:DIGital:WIDTh command), the channel numbering is modified as shown below. For example, if you specify the width as a 16-bit WORD, channels 101 and 102 are combined and addressed collectively as channel 101.
|
|
Bank 2 |
Bank 1 |
||||||
|
BYTE (8 Bits): |
Ch 204 |
Ch 203 |
Ch 202 |
Ch 201 |
Ch 104 |
Ch 103 |
Ch 102 |
Ch 101 |
|
WORD (16 Bits): |
Ch 203 |
Ch 201 |
Ch 103 |
Ch 101 |
||||
|
LWORd (32 Bits): |
Ch 201 |
Ch 101 |
||||||
If you specify an infinite sample count (default, INFinity or "0"), the bank will continue to capture data until you perform a stop operation using the [SENSe:]DIGital:MEMory:STOP command. If memory overflows, the newest data will overwrite the first (oldest) data stored. The most recent data is always preserved.
After specifying the desired sample count, you can use the [SENSe:]DIGital:MEMory:STARt command to start the buffered input operation.
For buffered input transfers, the oldest data is stored at index zero (0). You can use the [SENSe:]DIGital:MEMory[:DATA]? command to perform a non-destructive read of the data stored in memory. Or, use the [SENSe:]DIGital:MEMory:CLEar command to clear the memory.
You can use the [SENSe:]DIGital:MEMory[:DATA]:POINts? command to read the number of samples currently stored in memory.
The selected sample count is stored in volatile memory and will be set to 0 (continuous) when power is turned off or after a Factory Reset (*RST command).
Return Format
The query command returns the sample count for each channel specified. Multiple responses are separated by commas. For a continuous count ("0" or INFinity), the query command returns "0".
Examples
The following program segment sets the sample count on channels 101 and 201 on the module in slot 3.
CONF:DIG:WIDTH WORD,(@3101,3201)
!Width
= 16 bits
DIG:MEM:SAMP:COUN 200,(@3101,3201) !Sample
count = 200
DIG:MEM:ENAB ON,(@3101,3201) !Enable
buffered reads
DIG:MEM:STAR (@3101,3201) !Start
buffered reads
The following query returns the sample count on channels 101 and 201 on the module in slot 3.
DIG:MEM:SAMP:COUN? (@3101,3201)
Typical Response: 200,200
See Also
[SENSe:]DIGital:MEMory[:DATA]?
[SENSe:]DIGital:MEMory[:DATA]:ALL?
[SENSe:]DIGital:MEMory[:DATA]:POINts?