Yes. I saw that and wondered, as you did, if it referred to Thorpe's N-of-M coding.Hey @Diogenese, you got your eyes on?
N-of-M coding is directly tied to the arrival time of spikes from different "pixel" neurons although I would guess it also applies to auditory and other sensory neurons.
To get to N-of-M coding, there was a two step process. The first step was in realizing that the then "orthodox" spike rate coding was inefficient and error-prone. When a nerve fires, it transmits a burst of decreasing pulses, the pulse rate being a measure of the strength of the signal. Thorpe realized that measuring the rate was inefficient mainly because it involved using a redundant secondary source of the spike information, and it was error-prone because neuron firing at rates of less than 1/10th of a second is unreliable. As I've mentioned before, Thorpe found that the initial spike of a spike burst from an optical nerve carried all the necessary information.
Thorpe also noticed that the firing time was inverse to the amplitude of the excitatory energy - the stronger the signal, the sooner the nerve fired.
Hence the switch from rate coding to spike time coding.
So that leaves all M spikes from M neurons still being processed, which brings us to the second step.
The next step was the realization that the later-arriving spikes added little to the accuracy of the visual detection. In other words, accurate detection could be carried out from the first N pulses to arrive - N-of-M coding.
As you can see, Thorpe's N-of-M coding is all about spikes which arrive asynchronously.
I could find nothing in the Renesas article or in their patents suggesting the use of spikes.
This recent Renesas patent application uses MACs.
US2024054083A1 SEMICONDUCTOR DEVICE 20220808
A semiconductor device capable of shortening processing time of a neural network is provided. The memory stores a compressed weight parameter. A plurality of multiply accumulators perform a multiply-accumulation operation to a plurality of pixel data and a plurality of weight parameters. A decompressor restores the compressed weight parameter stored in the memory to a plurality of weight parameters. A memory for weight parameter stores the plurality of weight parameters restored by the decompressor. The DMA controller transfers the plurality of weight parameters from the memory to the memory for weight parameter via the decompressor. A sequence controller writes down the plurality of weight parameters stored in the memory for weight parameter to a weight parameter buffer at write timing.
That said, I haven't found out what their N:M refers to, and there is still 18 months of unpublished patent applications.