Coprocessor 15 is typically reserved for use as a system control coprocessor. For an MCR to coprocessor 15, it is possible to transfer the coprocessor data to the coprocessor on the ADDR and WDATA busses. To do this the coprocessor must drive GO on the coprocessor handshake signals for a number of cycles. For each cycle that the coprocessor responds with GO on the handshake signals, the coprocessor data is driven onto ADDR and WDATA as shown in Figure 5.4.