Serialization / Deserialization

ROHD-HCL implements a Serializer and Deserializer set of components that enable converting wide structures to a serialized narrow stream of data and vice-versa.

Serializer

The Serializer is a module that accepts a wider LogicArray deserialized for input data and optionally a Logic enable to allow for pausing serialization. While enable is high, the Serializer sequentially outputs chunks of data on the Logic serialized output until the entire LogicArray deserialized has been transferred to the output. At that point the Serializer raises Logic done. This process will continue until the Logic enable is lowered, allowing for back-to-back transfers of wide data over the Logic serialized stream. Alternatively, an optional input endCount can cause serialization to be halted earlier than the number of steps implied by the width of the deserialized input array. The semantics of endCount are that serialization will drive the done output on the ith step where i==endCount. The number of serialization steps in the current transfer is available in Logic count. Lowering enable will pause the transfer and raising it will continue from where it paused.

Deserializer

The Deserializer is a module that accepts a Logic serialized stream over a pre-defined length number of clocks. It outputs a LogicArray deserialized of the same length of Logic words that match the width of Logic serialized. Deserialization runs while Logic enable is high, and Logic done is emitted when deserialization is complete. This process will continue when Logic enable is high, allowing for back-to-back deserialization transfers of a narrow stream of data into wider (length) LogicArrays during length number of serialization steps (clocks while enable is high) for each transfer. Alternatively, the optional input last allows for earlier termination of deserialization (i.e., driving of the done output) meaning only the first n elements in the deserialized output array will contain meaningful data from the given transfer where n is the number of cycles up to the point at which last was driven. The number of serialization steps in the current transfer is available in Logic count. Lowering enable will pause the transfer and raising it will continue from where it paused.