Retinal Prosthesis Dissertation - Student Home Pages

5.3 Receiver schematics
In figure 47 the first block: “pulse_count_to_AER_stream receives from the sender
chip the AER stream formatted as address bits followed by a payload of 18 bits of
colour data. The 16 pixel image to be dealt with has 4 address bits associated with
the payload. This block converts the payload from a pulse count to a string of 50 bits
for each colour plane, retains the pixel address and outputs a 154 bit stream.
The second block “preform_for_electrodes” separates the planes of colour into three
separate streams with each plane of colour retaining the pixel address with which it
is associated, giving the potential for each plane of colour to be addressed separately.
The third block (produce_colour_data_streams) strips out the address bits and
continues the processing sequentially on each plane of colour data.
Block four (fully_extend_data_streams) packs the colour data into pixel length
streams to be fed into the routing stage. Block five, the routing stage
(produce_wire_outputs) has a twofold function (1) it routes the pixel streams to the
relevant inputs to the electrodes driving circuitry (2) it allows routing adjustments to
be made where necessary within the software environment.
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