The PEs had about 12,000 gates. It included four 64-bit registers, using an accumulator A, an operand buffer B and a secondary scratchpad S. The fourth, R, was used to broadcast or receive data from the other PEs. The PEs used a carry-lookahead adder, a leading-one detector for boolean operations, and a barrel shifter. 64-bit additions took about 200 ns and multiplications about 400 ns. The PE's were connected to a private memory bank, the PEM, which held 2,048 64-bit words. Access time was on the order of 250 ns The PEs used a load/store architecture.