ADC attributes

Scan Mode

The KMXF_ANALOG_MODULE_ADC_SCAN_MODE attribute defines the scan mode. The IPM-ADC offers eight different scan modes of sampling:

Constant	Description
VMXF_ANALOG_MODULE_ADC_SCAN_MODE_DISABLE	Scanning disabled. This mode may be used to start acquisition or sampling on many ADC channels before starting the scanning. No data is received while the scan mode is disabled.
VMXF_ANALOG_MODULE_ADC_SCAN_MODE_UNIFORM_CONTINUOUS	The A/D conversions are performed in sequential order for all selected channels. Only one channel at a time is converted at each period.
VMXF_ANALOG_MODULE_ADC_SCAN_MODE_UNIFORM_SINGLE	The A/D conversions are performed in sequential order for all selected channels only one time. Only one channel at a time is converting at each period. The conversions stop after the last selected channel.
VMXF_ANALOG_MODULE_ADC_SCAN_MODE_BURST_CONTINUOUS (default)	The A/D conversions are performed in sequential order for all selected channels. All selected channels are converted at each period as fast as possible (one channel each 4 microseconds).
VMXF_ANALOG_MODULE_ADC_SCAN_MODE_BURST_SINGLE	The A/D conversions are performed in sequential order for all selected channels only one time. All selected channels are converted at each period as fast as possible (one channel each 4 microseconds). The conversions stop after the last selected channel.
VMXF_ANALOG_MODULE_ADC_SCAN_MODE_UNIFORM_CONTINUOUS_EXT_TRIG	The A/D conversions are performed in sequential order for all selected channels. Only one channel at a time is converted at each external trigger pulse (falling edge of trigger input). The conversion period has no functionality is this mode.
VMXF_ANALOG_MODULE_ADC_SCAN_MODE_UNIFORM_SINGLE_EXT_TRIG	The A/D conversions are performed in sequential order for all selected channels only one time. Only one channel at a time is converted at each external trigger pulse (falling edge of trigger input). The conversions stop after the last selected channel. The conversion period has no functionality in this mode.
VMXF_ANALOG_MODULE_ADC_SCAN_MODE_BURST_CONTINUOUS_EXT_TRIG	The A/D conversions are performed in sequential order for all selected channels only one time. All selected channels are converted at each external trigger pulse (falling edge of trigger input) as fast as possible (one channel each 4 microseconds). The conversion period has no functionality is this mode.
VMXF_ANALOG_MODULE_ADC_SCAN_MODE_BURST_SINGLE_EXT_TRIG	The A/D conversions are performed in sequential order for all selected channels only one time. All selected channels are converted at each external trigger pulse (falling edge of trigger input) as fast as possible (one channel each 4 microseconds). The conversions stop after the last selected channel. The conversion period has no functionality is this mode.

Note: The trigger mode must be set to slave before changing the scan mode to any external trigger modes.

Conversion Period

The KMXF_ANALOG_MODULE_ADC_CONVERSION_PERIOD attribute defines the conversion period. The attribute value resolution is based on the timebase resolution.

This period value represents:

Burst Modes: The time between the first sample of a burst (all selected channels) and the first sample of the next burst. The smallest sampling interval depends on the speed of ADC used and on the number of channels selected. Equation: Smallest Period (micro-seconds) = Channel number * 4.
Uniform Modes: The time between each sample (each selected channel).

The supported range is:

Range	Value (microsecond)
Minimum	4
Maximum	4294967295

Default value: 100000 microseconds.

Note: The conversion period has no functionality with any external trigger scan modes.

Data Format

The KMXF_ANALOG_MODULE_ADC_DATA_FORMAT attribute defines the data format. Float format is the default one and the simplest to use. Raw data is also available. Raw data will need a little less CPU from the device as no floating point conversion is done.

The supported values are:

Constant	Description
VMXF_ANALOG_MODULE_ADC_DATA_FORMAT_RAW_SIGNED	Signed (Binary two’s complement)
VMXF_ANALOG_MODULE_ADC_DATA_FORMAT_RAW_UNSIGNED	Unsigned (Straight binary)
VMXF_ANALOG_MODULE_ADC_DATA_FORMAT_FLOAT (default)	Floating point

Trigger Mode

The KMXF_ANALOG_MODULE_ADC_TRIGGER_MODE attribute defines the trigger mode. The external trigger input/output is used to synchronize the sampling with other IPM-ADC modules, or with any other source. When set to master, a 500ns pulse will be output when the time to scan is reached. When set to slave and an “EXT_TRIG” mode is used (see Scan Mode, the external trigger is used as an input.

The supported values are:

Constant	Description
VMXF_ANALOG_MODULE_ADC_TRIGGER_MASTER	Master (output trigger)
VMXF_ANALOG_MODULE_ADC_TRIGGER_SLAVE (default)	Slave (input trigger)

Note: The trigger mode is read-only to Slave if the scan mode is set to any external trigger modes.

Calibration Mode

The KMXF_ANALOG_MODULE_ADC_CALIBRATION_MODE attribute defines the calibration mode. When enabled, internal power source will be connected to the input.

The supported values are:

Constant	Description
VMXF_ANALOG_MODULE_ADC_CALIBRATION_MODE_DISABLE (default)	Calibration disabled. External value will be returned.
VMXF_ANALOG_MODULE_ADC_CALIBRATION_MODE_0	0 Volt
VMXF_ANALOG_MODULE_ADC_CALIBRATION_MODE_306250	0.30625 Volt
VMXF_ANALOG_MODULE_ADC_CALIBRATION_MODE_612500	0.6125 Volt
VMXF_ANALOG_MODULE_ADC_CALIBRATION_MODE_1225000	1.225 Volt
VMXF_ANALOG_MODULE_ADC_CALIBRATION_MODE_2450000	2.45 Volt
VMXF_ANALOG_MODULE_ADC_CALIBRATION_MODE_4900000	4.9 Volt

Input Range

The KMXF_ANALOG_MODULE_ADC_INPUT_RANGE attribute defines the input range. The input range must match the dip switches setting of the module.

The supported values are:

Constant	Description
VMXF_ANALOG_MODULE_ADC_INPUT_RANGE_5v	-5V to 5V
VMXF_ANALOG_MODULE_ADC_INPUT_RANGE_0v_5v	0V to 5V
VMXF_ANALOG_MODULE_ADC_INPUT_RANGE_10v (default)	-10V to 10V
VMXF_ANALOG_MODULE_ADC_INPUT_RANGE_0v_10v	0V to 10V
VMXF_ANALOG_MODULE_ADC_INPUT_RANGE_2_5v	-2.5V to 2.5V
VMXF_ANALOG_MODULE_ADC_INPUT_RANGE_0v_2_5v	0V to 2.5V

Channel Differential Selection

The KMXF_ANALOG_MODULE_ADC_CHN_DIFF_SELECTION attribute defines the channel differential selection. The IPM-ADC has up to 32 single-ended or up to 16 differential channels. Each channel pair (channel 0-16, 1-17, 2-18, etc.) may be set to single-ended or to differential mode independently. This attribute is a 16-bit mask that selects differential channels.

The bit #0 represents channel pairs 0-16, bit #1 represents the channel pairs 1-17, …, bit #15 represents the channel pairs 15-31.

Note: When a channel pair is set to differential, only the first channel of the pair may be selected by KMXF_ANALOG_MODULE_ADC_CHN_SELECTION attribute. The second channel of a pair will be unselected automatically if it is already selected.

Default value: 0xffff (16 differential channels).

Channel Selection

The KMXF_ANALOG_MODULE_ADC_CHN_SELECTION attribute defines the channel selection. The IPM-ADC has up to 32 single-ended or up to 16 differential channels. Each channel may be selected independently. This attribute is a 32-bit mask that selects channels. When a channel pair is set to differential, only the first channel of the pair may be selected.

Ex. If the channel pair 0-16 is set to differential (Channel Differential Mask = 0x0001), the channel 0 (Channel Selection Mask = 0x00000001) must be used to enable the pair. An error will occur if bit 16 is present. To add channel 1 and 17 that are set in single ended mode, the Channel Selection Mask will be 0x00020003.

Note: When a channel pair is set to differential, only the first channel of the pair may be selected by KMXF_ANALOG_MODULE_ADC_CHN_SELECTION attribute. The second channel of a pair will be unselected automatically if it is already selected.

Default value: 0x0000ffff (16 channels).

RX FIFO Aging Timeout

The KMXF_ANALOG_MODULE_ADC_FIFO_AGING attribute defines the FIFO aging timeout value for a receiver channel. It defines the longest delay that a received word can wait in the hardware FIFO before a receive interrupt is generated. The attribute value resolution is based on the timebase resolution. A RX FIFO Aging Timeout value of 0 disables the aging timeout. The attribute value is rounded down to step of 512 microseconds.

The supported range is:

Range	Value (microsecond)
Minimum	0 (disabled)
Maximum	65024

Default value: 8192 microseconds.

Note: MX Foundation takes care of initializing this attribute using the optimal value. It is not recommended to change to this attribute unless told to do so by a MAX Technologies support engineer.

RX FIFO Almost Full Threshold

The KMXF_ANALOG_MODULE_ADC_FIFO_AF attribute holds the almost full threshold for a receiver channel. This attribute value determines the number of received words that must be accumulated in the receive hardware FIFO before an interrupt is generated.

The supported range is:

Range	Value (16-bit word)
Minimum	1
Maximum	2048

Default value: 16.

Note: MX Foundation takes care of initializing this attribute using the optimal value. It is not recommended to change to this attribute unless told to do so by a MAX Technologies support engineer.

Gain

The KMXF_ANALOG_CHN_ADC_GAIN attribute holds the hardware gain for a channel. The gain must be chosen depending on the type of signal that will be sampled on the channel. For example, if the input range is set to +/-5V, and the input signal is known to be a +/-1V signal, a gain of 4 could be applied to the input, so the ADC range (with gain of 4, +/-1.25V) would be more adapted to the signal.

The supported values are:

Constant	Gain
VMXF_ANALOG_CHN_ADC_GAIN_1 (default)	1
VMXF_ANALOG_CHN_ADC_GAIN_2	2
VMXF_ANALOG_CHN_ADC_GAIN_4	4
VMXF_ANALOG_CHN_ADC_GAIN_8	8

DAC attributes

Output Range

The KMXF_ANALOG_MODULE_DAC_OUTPUT_RANGE attribute defines the output range. The output range must match the jumpers setting of the module.

The supported values are:

Constant	Description
VMXF_ANALOG_MODULE_DAC_OUTPUT_RANGE_5v (default)	-5V to 5V
VMXF_ANALOG_MODULE_DAC_OUTPUT_RANGE_10v	-10V to 10V

Common attributes

Calibration Slope

The KMXF_ANALOG_CHN_CALIBRATION_SLOPE attribute holds the calibration slope for a channel. The “m” in equation “mx + b”. This is a floating point attribute.

The slope could take a value in the following range:

Range	Value (V)
Minimum	-10000.0
Maximum	10000.0

Default value: 1.0.

Calibration Offset

The KMXF_ANALOG_CHN_CALIBRATION_OFFSET attribute holds the calibration offset for a channel. The “b” in equation “mx + b”. This is a floating point attribute.

The offset could take a value in the following range:

Range	Value (V)
Minimum	-10000.0
Maximum	10000.0

Default value: 0.0.