Table Of Contents
Binary MLS (G Dataflow)
Generates a maximum length sequence (MLS) of ones and zeros using a modulo-2 primitive polynomial of a specific order.
reset
A Boolean that controls the reseeding of the binary MLS generator after the first call of the node.
| True | Accepts a new seed and begins producing binary MLS samples based on seed. |
| False | Maintains the initial internal seed state and resumes producing binary MLS samples as a continuation of the previous binary MLS. |
Default: False
polynomial order
Order of the modulo-2 primitive polynomial.
If the input value is out of range, this node truncates the polynomial order to [3, 62].
Default: 31
seed
Number that this node uses to initialize the binary MLS generator.
This node initializes the binary MLS generator using seed if reset is True or if this is the first call of the node.
| seed is greater than 0 | Generates binary MLS samples based on the seed value. For multiple calls to the node, the node accepts or rejects new seed inputs based on the reset value. |
| seed is less than or equal to 0 | Generates a random seed value and produces binary MLS samples based on that seed value. For multiple calls to the node, if seed remains less than or equal to 0, the node ignores the reset input and produces binary MLS samples as a continuation of the initial binary MLS. |
Default: -1
error in
Error conditions that occur before this node runs.
The node responds to this input according to standard error behavior.
Standard Error Behavior
Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.
Default: No error
sample rate
Sample rate in samples per second.
This input is available only if you configure this node to return a waveform.
Default: 1000
samples
Number of samples in the signal.
samples must be greater than 0. Otherwise, this node returns an error.
Default: 1000
t0
Timestamp of the output signal. If this input is unwired, this node uses the current time as the timestamp of the output signal.
This input is available only if you configure this node to return a waveform.
MLS
error out
Error information.
The node produces this output according to standard error behavior.
Standard Error Behavior
Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.
Algorithm for Calculating MLS
This node uses a modulo-2 primitive polynomial to generate the binary Maximum Length Sequence (MLS). The MLS is periodic with a period of 2 n - 1. Each period consists of 2 n - 1 ones and 2 n - 1 - 1 zeros, where n is the polynomial order. The MLS is spectrally flat, with a near-zero DC term.
For example, if the polynomial order is 4, this node uses the polynomial g(p) = p 4 + p + 1 to generate the MLS with a period of 15 in the following manner:
where is the modulo-2 addition, and a0, a1, a2 and a3 are the shift registers.
The following 15-point sequence comprises each period of the generated sequence: 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1. However, the starting point might be different for each sequence.
The MLS is a type of Pseudo-Random Binary Sequence (PRBS).
Where This Node Can Run:
Desktop OS: Windows
FPGA: Not supported
Web Server: Not supported in VIs that run in a web application