ThinkTank Notes

1. (a) Which output control signal is activated after every six oscillator periods while fetching the external program memory and almost remains high during internal program execution? (i) ALE  (ii) PSEN  (iii) EA  (iv) All of the above (a) The correct option is ( i )  ALE (Address Latch Enable) . ALE is activated after every six oscillator periods while fetching the external program memory. It remains high during internal program execution to latch the address from the program counter (PC) onto the external address bus. (b) What is the bit transmitting or receiving capability of mode 1 in serial communication? (i) 8 bits (ii) 10 bits (iii) 11 bits (iv) 12 bits (b) The correct option is ( i )  8 bits . Mode 1 in serial communication of the 8051 microcontroller supports 8-bit data transmission. It uses a start bit, followed by 8 data bits, and optionally a parity bit and stop bit. (c) Which byte has the capability to interrupt the slave when SM2 bit is assigned ...

 Microprocessor PYQ-2020 1 (a) Which among the below mentioned functions does not belong to the category of alternate functions usually performed by Port 3 (Pins 10-17)? (i) External interrupts (ii) Internal interrupts (iii) Serial ports  (iv) Read/Write control signals (b) Why are the resonators not preferred for an oscillator circuit of 8051?  (i) Because they do not avail for 12 MHz higher order frequencies  (ii) Because they are unstable compared to quartz crystals (iii) Because cost reduction due to its utility is almost negligible in comparison to total cost of microcontroller board  (iv) All of the above (c) Which serial modes passes the potential to support the multi-processor type of communication? (i) Modes 0 & 1 (ii) Methods 1 & 2 (i) Methods 2 & 3 (iv) All of the above (D) Which flag allows to carry out the signed as well as unsigned addition and subtraction operations? (i) CY  (ii) OV  (iii) AC  (iv) FO (e) Which among the...