The following attributes are available for the devices supporting dedicated discrete interface.

The following discrete attributes are available only for the IO-MULTI-EH device.

Number of Ports

The KMXF_DISCRETE_NUMPORT read only attribute specify the number of digital I/O ports supported by a device.

Falling Edge

The KMXF_DISCRETE_RX_EDGE_FALLING attribute holds the edge falling attribute.

This attribute holds the falling edge capture bit mask. Each bit allows capturing the discrete input port value when a falling edge is detected on the bits set to “1” in this attribute mask.

Not available on IPM-DIO-48 module.

Default value: Falling edge capture enabled for each port.

Rising Edge

The KMXF_DISCRETE_RX_EDGE_RISING attribute holds the edge rising attribute.

This attribute holds the rising edge capture bit mask. Each bit allows capturing the discrete input value when a rising edge is detected on the bits set to “1” in this attribute mask.

Not available on IPM-DIO-48 module.

Default value: Rising edge capture enabled for each port.

Pulse Width Filter

The KMXF_DISCRETE_RX_PULSE_WIDTH_FILTER attribute defines the minimum pulse width value needed for the transition to be valid (the effective precision is 10 ns, the value is truncated to multiple of 10 ns). It is useful to filter transitions that are caused by line bouncing or glitch.

The time at which the data is written in the RX FIFO is delayed by this value. It is recommended to wait this delay after having changed the attribute before enabling the RX FIFO (when an acquisition is started).
This attribute is not available on IPM module discrete.

The supported range is:

Range	Value (ns)
Minimum	10
Maximum	1000000000

Note: Hardware line sampling is 100 MHz (10 ns). If the line transition is faster than this value, the transition will not be detected.

Default value: 100 ns

Sampling Period

The KMXF_DISCRETE_RX_FIFO_SAMP_PERIOD attribute defines the RX FIFO sampling period value, in nanosecond (the effective precision is 10 ns).

This attribute is useful to limit the number of transitions written in the RX FIFO. The edge detection is performed at 100 MHz but the module accumulates all transitions and writes maximum one at each sampling period. The precision of the time tag is equal to the sampling period value. The sampling period starts at the next microsecond boundary following the write to this attribute.
This attribute is not available on IPM module discrete.

The supported range is:

Range	Value (ns)
Minimum	10
Maximum	1000000000

Default value: 100 ns

Sampling Inter Edge

The KMXF_DISCRETE_RX_FIFO_SAMP_INTER_EDGE_ENABLE attribute allows detection of all edges between sampling points.
This attribute is not available on IPM module discrete.

The supported values are:

Constant	Value
VMXF_ENABLE	Allow detection of all edges between sampling points.
VMXF_DISABLE	When the value changes between the current sampling point and the previous, the value will be written in the RX FIFO. (default)

Loopback mode

The KMXF_DISCRETE_TX_RX_TEST_LB attribute holds the actual port internal loopback state. When the loopback mode is enabled, the data received comes from the corresponding transmitter channel instead of the normal behavior where the received data comes from the receiver line interface. This feature is intended for a demo application or for test purposes. When enabled, the module’s RX channel receives data transmitted on the TX channel. Transmissions are still sent on the TX line when loopback mode is enabled.
This attribute is not available on IPM module discrete.

The supported values are:

Constant	Value
VMXF_ENABLE	The input pins are internally routed to the output pins (input pin 0 to output pin 0, …).
VMXF_DISABLE	The signals are received from external lines. (default)

RX Timetag Enable

The KMXF_DISCRETE_MODULE_RX_TIMETAG_ENABLE and KMXF_DISCRETE_RX_TIMETAG_ENABLE (MXF_MODULE_ASYNC) attributes define the RX time tag enable state.

Not available on IPM-DIO-48 and IPM-DIO-24 module.

The supported values are:

Constant	Value
VMXF_ENABLE	The reception time tag is returned in the records based on the active timebase. (default)
VMXF_DISABLE	No time tag is returned (value zero is returned)

RX FIFO Aging Timeout

The KMXF_DISCRETE_MODULE_RX_FIFO_AGING and KMXF_DISCRETE_RX_FIFO_AGING (MXF_MODULE_ASYNC) attributes define the FIFO aging time-out value.

It defines the longest delay, based on the timebase resolution, that a received word can wait in the hardware FIFO before a receive interrupt is generated to the firmware. The attribute value resolution is based on the timebase resolution. A RX FIFO Aging Timeout value of 0 disables the aging timeout.

The supported range is:

Module	Range (microsecond)	Default (microsecond)	Note
MXF_MODULE_ASYNC	0 - 16320	8192	Value is rounded down to step of 64 microseconds
MXF_MODULE_DIOFIFO24DIFF	0 - 7680	4096	Value is rounded down to step of 512 microseconds
MXF_MODULE_DIOFIFO48	0 - 7680	4096	Value is rounded down to step of 512 microseconds
Others	0 - 25500	8000	Value is rounded down to step of 100 microseconds

RX FIFO Almost Full Treshold

The KMXF_DISCRETE_MODULE_RX_FIFO_AF and KMXF_DISCRETE_RX_FIFO_AF (MXF_MODULE_ASYNC) attributes hold 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:

Module	Range	Default
MXF_MODULE_ASYNC	1 - 255 (16-bit word)	16
MXF_MODULE_DIOFIFO24DIFF	1 - 127 (48-bit word)	2
MXF_MODULE_DIOFIFO48	1 - 16 (48-bit word)	2
Others	1 - 1023 (16-bit word)	24

TX FIFO Almost Full Threshold

The KMXF_DISCRETE_MODULE_TX_FIFO_AF and KMXF_DISCRETE_TX_FIFO_AF (MXF_MODULE_ASYNC) attributes hold the almost full threshold for a transmitter channel. This attribute value determines the number of transmit 16-bit words that are to be queued in the transmit hardware FIFO. The transmit interrupt will be cleared automatically once this threshold is reached.

The supported range is:

Module	Range	Default
MXF_MODULE_ASYNC	2 - 255 (16-bit word)	32
MXF_MODULE_DIOFIFO24DIFF	2 - 127 (48-bit word)	8
MXF_MODULE_DIOFIFO48	2 - 16 (48-bit word)	8
Others	2 - 1023 (16-bit word)	48

TX FIFO Almost Empty Threshold

The KMXF_DISCRETE_MODULE_TX_FIFO_AE and KMXF_DISCRETE_TX_FIFO_AE (MXF_MODULE_ASYNC) attributes hold the almost empty threshold for a transmitter channel. The transmit interrupt is generated whenever the number of 16-bit words remaining in the transmit hardware FIFO is less or equal to the value specified by this attribute. The software embedded process will then be able to react and fill in the transmit FIFO.

The supported range is:

Module	Range	Default
MXF_MODULE_ASYNC	1 - 254 (16-bit word)	16
MXF_MODULE_DIOFIFO24DIFF	1 - 126 (48-bit word)	6
MXF_MODULE_DIOFIFO48	1 - 15 (48-bit word)	6
Others	1 - 1022 (16-bit word)	24

RX Single Ended Threshold

The KMXF_DISCRETE_MODULE_SINGLE_ENDED_THRESHOLD attribute holds the Rx threshold value for a receiver channel when configure in single ended. This is a floating point attribute. This attribute is available only for FM664, FM429, FlexMobile and FlexMAX device.

On FlexMobile, the threshold is calibrated with a pull-up resistor value of 4.7 kOhm, which is the recommended value. The hysteresis is approximately 1.2V (+/-0.6V around the threshold value).

This attribute is not available on IPM module discrete.

The supported range is:

DEVICE	Range (volt)	Default (volt)
FlexMobile	1.0 - 48.0	8.5
Others	0.0 - 5.0	1.64

IO Direction

The KMXF_DISCRETE_DIRECTION attribute holds the direction (input/output) of IO ports for bidirectional channel. This is a bitmask field where the bit 0 value represents port 0, the bit 1 value represents port 1 and so on. A bit value of 1 means that the corresponding port is setup as an output port and a value of 0 means that the port is setup as an input port. This attribute is available only for bi-directional discrete channel.

_Default value: 0x0000 (all ports setup as input ports)

Electrical Selection

The KMXF_DISCRETE_ELECTRICAL_SELECTION attribute holds the actual channel electrical selection. When the electrical selection is set to default, all electrical attributes below are set to a default value and are read only. To modify any of these attributes, set electrical selection to custom.

Constant	Value
VMXF_DISCRETEEH_MULTI_ELECTRICAL_SELECT_DEFAULT	Select default electrical parameters (default)
VMXF_DISCRETEEH_MULTI_ELECTRICAL_SELECT_CUSTOM	Select custom electrical parameters

TX Differential Voltage High

The KMXF_DISCRETE_TX_DIFF_VOLTAGE_HIGH attribute defines the high TX differential voltage value. This is a floating point attribute. To modify this attribute value, the KMXF_DISCRETE_ELECTRICAL_SELECTION attribute must be set to custom.

This attribute is only available on Multi Enhanced channel.

Device Type	Revision	MXF Version	Range (Volt)
FlexMulti 629	Up to 2.4	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.1 – +6.1
	2.5 and later	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.5 – +6.5
FlexMulti 1553	Up to 3.2	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.1 – +6.1
	3.3 and later	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.5 – +6.5
FlexMulti 429 FlexMulti 664 FlexMulti	Up to 3.0	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.1 – +6.1
	3.1 and later	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.5 – +6.5

Default value: +2.50 volt

TX Differential Voltage Low

The KMXF_DISCRETE_TX_DIFF_VOLTAGE_LOW attribute defines the low TX differential voltage value. This is a floating point attribute. To modify this attribute value, the KMXF_DISCRETE_ELECTRICAL_SELECTION attribute must be set to custom.

This attribute is only available on Multi Enhanced channel.

Device Type	Revision	MXF Version	Range (Volt)
FlexMulti 629	Up to 2.4	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.1 – +6.1
	2.5 and later	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.5 – +6.5
FlexMulti 1553	Up to 3.2	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.1 – +6.1
	3.3 and later	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.5 – +6.5
FlexMulti 429 FlexMulti 664 FlexMulti	Up to 3.0	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.1 – +6.1
	3.1 and later	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.5 – +6.5

Default value: -2.50 volt

TX Voltage Offset

The KMXF_DISCRETE_TX_VOLTAGE_OFFSET attribute defines the TX voltage offset. This is a floating point attribute. To modify this attribute value, the KMXF_DISCRETE_ELECTRICAL_SELECTION attribute must be set to custom.

This attribute is only available on Multi Enhanced channel.

Device Type	Revision	MXF Version	Range (Volt)
FlexMulti 629	Up to 2.4	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.1 – +6.1
	2.5 and later	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.5 – +6.5
FlexMulti 1553	Up to 3.2	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.1 – +6.1
	3.3 and later	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.5 – +6.5
FlexMulti 429 FlexMulti 664 FlexMulti	Up to 3.0	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.1 – +6.1
	3.1 and later	Up to 4.2.5	-5.0 – +5.0
		4.3.0 to 4.4.1	-6.0 – +6.0
		4.4.2 and later	-6.5 – +6.5

Default value: 2.50 volt

TX Slew Rate Selection

The KMXF_DISCRETE_TX_SLEW_RATE_SELECTION attribute defines the TX slew rate selection. MX Foundation automatically sets the default slew rate to its minimum value. When the default option is selected, the KMXF_DISCRETE_TX_SLEW_RATE attribute will be read only. Otherwise, the custom option allows specifying the slew rate with the KMXF_DISCRETE_TX_SLEW_RATE attribute. To modify this attribute value, the KMXF_DISCRETE_ELECTRICAL_SELECTION attribute must be set to custom.

This attribute is only available on Multi Enhanced channel.

Constant	Value
VMXF_DISCRETEEH_MULTI_TX_SLEW_RATE_SELECT_DEFAULT	Select default slew rate parameter (default)
VMXF_DISCRETEEH_MULTI_TX_SLEW_RATE_SELECT_CUSTOM	Select custom slew rate parameter

TX Signal Slew Rate

The KMXF_DISCRETE_TX_SLEW_RATE attribute defines the TX signal slew rate. MX Foundation automatically sets the default slew rate to its minimum value. When the default option is selected, the KMXF_DISCRETE_TX_SLEW_RATE attribute will be read only. Otherwise, the custom option of the KMXF_DISCRETE_TX_SLEW_RATE_SELECTION attribute allows specifying the slew rate with this attribute.

This attribute is only available on Multi Enhanced channel.

The supported range is:

Module	Range (nsec/volt)	Default (nsec/volt)	Formula
MXF_MODULE_MULTI_EH	2.0 - 13429.5	2.0	(204800/1.22) / (n*3.125) with 4 ≤ n ≤ 26856

RX Differential Voltage Threshold

The KMXF_DISCRETE_RX_DIFF_VOLTAGE_THRESHOLD attribute defines the RX differential voltage threshold. This is a floating point attribute. To modify this attribute value, the KMXF_DISCRETE_ELECTRICAL_SELECTION attribute must be set to custom.

This attribute is only available on Multi Enhanced channel.

Range	Value (Volt)
Minimum	0.0
Maximum	25.0

Resolution: 0.05224 volt Default value: 0.20 volt