8051 microcontroller

6. (5 points) Assume a keypad is connected to 8051 as shown, If the content of register A after executing the code sequence below is equal to OFAH, identify the key(s) pressed if any. Explain your answer. 8051 KeyPad MOV PO,#0FFH 0 1 2 3 MOV P1,#OBDH P. MOV A,PO 4 5 6 7 8 9 A B P.P.P.P. 90.37 C D E F 0.0 0.1 P. 0.2 1.3 1.21.1 1.0