Interface test circuitry and methods

An apparatus comprising:

• conductors to carry test pattern signals from a transmitting apparatus, the test pattern signals having test properties that have been embedded;
• a decoder to receive and decode the test pattern signals with embedded test properties;
• and
• receiver test circuitry to:
• receive the test pattern signals with embedded test properties, the test properties including a sequence of class signatures, the class signatures representing a partition of all possible codewords into subsets, the test properties defining types of test patterns to be transmitted,
• extract the embedded test properties from the test pattern signals, the test pattern signal including a sequential pattern of codewords that have been modified by transmitter test circuitry in order to embed the test properties in the codewords, and
• determine whether the extracted test properties match a set of expected test properties to determine whether one or more errors have occurred;
• wherein the receiver test circuitry includes:
• test encoding functions to provide encoded signals in response to bits from a first group of positions of signal sections of the test pattern signals, and
• circuitry to create expected sequences of class signatures in response to the encoded signals and control signals, the expected sequences of class signatures being used in determining whether the extracted test properties match the expected test properties.

A system comprising:

• a channel;
• a transmitter coupled with the channel including transmitter test circuitry, an encoder, and one or more multiplexers to:
• obtain a set of test properties for testing of the channel, the test properties including a sequence of class signatures, the class signatures representing a partition of all possible codewords into subsets, the test properties defining types of test patterns that may be transmitted to a receiver,
• embed the set of test properties in test pattern signals using the one or more multiplexers, the test pattern signals being encoded by the encoder, wherein the test pattern signals includes a sequential pattern of codewords that are modified by the transmitter test circuitry in order to embed the test properties in the codewords, and
• transmit the test pattern signals with the embedded test properties to the channel, the transmitter test circuitry further including test encoding functions to provide encoded bits in response to bits from a stream of signals and class generating functions to provide the sequence of class signatures in response to the encoded bits and control signals;
• and
• a receiver coupled with the channel including:
• a decoder to receive and decode the test pattern signals with embedded test properties;
• and
• receiver test circuitry coupled to the channel to:
• receive the test pattern signals with embedded test properties,
• extract the embedded test properties from the test pattern signals, and
• determine whether the extracted test properties match a set of expected test properties to determine whether one or more errors have occurred,
• wherein the receiver test circuitry includes:
• test encoding functions to provide encoded signals in response to bits from a first group of positions of signal sections of the test pattern signals, and
• circuitry to create expected sequences of class signatures in response to the encoded signals and control signals, the expected sequences of class signatures being used in determining whether the extracted test properties match the expected test properties.