Bit sequence generator and apparatus for calculating a sub-rate transition matrix and a sub-rate initial state for a state machine of a plurality of state machines

A system for performing automated test, the system comprising a bit sequence generator that comprises:

• a multiplexer configured to output an output bit sequence by successively selecting a respective bit of the output bit sequence from a plurality of time-interleaved bit sequences, wherein the output bit sequence is defined by a generating function and an initial state of the generating function;
• and
• a plurality of state machines coupled with the multiplexer and configured to generate the plurality of time-interleaved bit sequences, wherein each of the plurality of state machines is configured to generate a respective time-interleaved bit sequence of the plurality of time-interleaved bit sequence during a time step,
• wherein a first state machine of the plurality of state machines is configured to generate a first time-interleaved bit sequence of the plurality of time-interleaved bit sequences by generating a respective bit of the first time-interleaved bit sequence during a corresponding time step based on a) at least one preceding bit generated by the first state machine during a preceding time step, b) the generating function, and c) the initial state of the generating function, and independent from another time-interleaved bit sequence generated by another state machine of the plurality of state machines, wherein first time-interleaved bit sequence is generated in a first sub bit rate,
• wherein further the first state machine comprises a serializer that is configured to:
• serialize a state sequence of the first respective state machine;
• select a respective bit of the first time-interleaved bit sequence from the state sequence;
• and provide the first time-interleaved bit sequence in a serial manner with an intermediate bit rate, wherein the intermediate bit rate is equal to the first sub bit rate multiplied with a first predefined number of bits of the first time-interleaved bit sequence.

A method of generating an output bit sequence defined by a generating function and an initial state of the generating function, the method comprising:

• generating a plurality of time-interleaved bit sequences through a plurality state machines, wherein a respective time-interleaved bit sequence of the plurality of time-interleaved bit is generated by a respective state machine of the plurality state machines in an sub bit rate, wherein generating the respective time-interleaved bit sequence comprises:
• during a time step,
• (a) receiving, in an intermediate bit rate, a state sequence of the respective state machine that comprises a plurality of state bits in a serial manner;
• and
• (b) selecting a respective bit of the respective time-interleaved bit sequence from the state sequence,
• wherein the generating the respective time-interleaved bit sequence is based on at least one bit generated during a preceding time step,
• the generating function,
• the initial state of the generating function, and
• is independent from another generated time-interleaved bit sequence of the plurality of time-interleaved bit sequences;
• and
• wherein the intermediate bit rate is equal to the sub bit rate multiplied with a predefined number of bits of the respective time-interleaved bit sequence;
• and
• successively selecting one bit from the plurality of time-interleaved bit sequences to generate the output bit sequence.