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Encodes a sequence of data words non-systematically using the Bose-Chaudhari-Hocquenghem (BCH) algorithm. In the encoded code words, the whole data word sequence might not be explicitly present. The code word is generated as a finite field polynomial multiplication of the data word and the generator polynomial.


input bit stream

Bit sequence representing the data bits to encode. Use the bits generated by MT Generate Bits to produce this bit stream or wire a custom data bit stream to this parameter.


To ensure that the output bit stream returned by this node corresponds to the entire message, set the length of input bit stream to be an integer multiple of the data word length k . If the length of input bit stream is not an integer multiple of k, the last {length(input bit stream) modulo k} bits are buffered in the encoder. These bits are added to the beginning of the incoming bit stream during the beginning of the next iteration if reset? is set to FALSE.



Values of the code word length (n), data word length (k), and error correcting capacity (t), in bits. The n, k, and t values for BCH encoding are interrelated such that specifying two values constrains the third value. Select from a set of well-known (n,k,t) triples that are widely used for BCH encoding or specify an arbitrary triple by entering three comma-separated integers. The encoding scheme takes in a bit data word of k bits and produces a code word of n bits.

Code Word Length Limits

Default: 7, 4, 1


error in

Error conditions that occur before this node runs. The node responds to this input according to standard error behavior.

Default: no error



A Boolean that determines whether the internal state of the encoder is cleared.

TRUE Clears any buffered bits from previous iterations. Also initializes the Galois field structure corresponding to the BCH n, k, t values.
FALSE Continues encoding from the previous iteration. Any buffered bits from the previous iteration are added to the beginning of the input bit stream prior to encoding.

Default: TRUE


output bit stream

Bit sequence encoded by this node.


error out

Error information. The node produces this output according to standard error behavior.