P2 is a 8 - way I/On with internal pull ups, P2 output buffer can be driven (absorption or output current) 4, TTL logic gate circuit. In the end,.11 n wrote, through an internal pull-up resistor to the end of n to a high level, this can be used as input n, input n is used, because of the internal pullups, an externally being pulled low will source current ("(1)" in the external data access the external program memory or 16 bit memory address (such as the implementation of the MOVX@DPTR instruction), P2 sends a high 8 bit address data. In interviews with 8 of the external data memory address (such as the implementation of MOVX@RI directive), P2 content (i.e., not the daily special function register (SFR) in the contents of the R2 register), in the arch access does not change during.Flash programming andverification, P2 also receives the high-order address bits and the control signal