First/second memories hold rows of N weight/data words. Each of N processing units (PU) of index J have a register, an accumulator having an output, an arithmetic unit that performs an operation thereon to accumulate a result, the first input receives the output of the accumulator, the second input receives a respective first memory weight word, the third input receives a respective data word output by the register, and multiplexing logic receives a respective second memory data word and a data word output by the register of PU J−1 and outputs a selected data word to the register. PU J−1 for PU 0 is PU N−1. The multiplexing logic of PU N/4 also receives the data word output by the register of PU (3N/4)−1. The multiplexing logic of PU 3N/4 also receives the data word output by the register of PU (N/4)−1.