The design in single_buffer.py uses an Object FIFO of_in to transfer data from producer tile ComputeTile2 to consumer tile ComputeTile3. The Object FIFO has a depth of 1 which describes a single buffer between the two tiles as shown in the figure below.
Both the producer and the consumer processes in this design have trivial tasks. The producer process running on ComputeTile2 acquires the single buffer and writes 1 into all its entries before releasing it for consumption. The producer process running on ComputeTile3 acquires the single buffer and immediately releases it back for the producer.
To have this design use a double, or ping-pong, buffer for the data transfer instead, the user need only set the depth of the Object FIFO to 2. No other change is required as the Object FIFO lowering will take care of properly cycling between the ping and pong buffers. To change the depth of of_in the user should write:
of_in = object_fifo("in", ComputeTile2, ComputeTile3, 2, tile_ty) # double bufferThis change effectively increases the number of available resources of the Object FIFO as is shown in the figure below:
All examples available in the programming_examples contain this data movement pattern.