8. Name the special functions registers available in 8051. Accumulator B Register Program status Word. Stack pointer. Data pointer Port 0 Port 1 Port 2 Port 3 Interrupt priority control register. Interrupt enable control register. 9. Explain the register IE format of 8051. EA ET ES ET EX ET EX EA- Enable all control bit. ET- Timer 2 interrupt enable bit. ES- Enable serial port control bit. ET- Enable Timer control bit. EX1-Enable external interrupt control bit. ET0-Enable Timer control bit. EX0-Enable external interrupt control bit.