8085 Microprocessor Question & Answers October 11, 2021 By WatElectronics This article lists 100+ 8085 Microprocessor MCQs for engineering students. All the 8085 Microprocessor Questions & Answers given below include a hint and a link wherever possible to the relevant topic. This is helpful for users who are preparing for their exams, interviews, or professionals who would like to brush up their fundamentals on 8085 Microprocessor 8085 Microprocessor is an 8-bit programmable IC or integrated circuit invented by Intel in the year 1977. This microprocessor uses NMOS technology and it is pronounced “eighty-eighty-five” microprocessor. This microprocessor has the capabilities of decision-making & computing like the CPU of a personal computer. The configuration of 8085 is available with data bus - 8-bit, address bus - 16-bit, a 16-bit based program counter (PC), stack pointer -16-bit, 8-bit registers - 6 which are arranged in BC, HL & DE pairs and needs 5V supply at 3.2 MHZ 1-phase CLK. The functional unit 8085 microprocessor includes ALU, accumulator, the program counter (PC), the stack pointer (SP), general-purpose register, flag register, temporary register, address bus, data bus, interrupt control, serial I/O control, etc. The applications of the 8085 microprocessor include almost all electronic devices which include printers, mobiles, washing machines, and also in superior applications such as flights, satellites, radars, etc. 1). How many pins of 8085 microprocessor includes? 40 35 28 64 None Hint 2). How many output pins an 8085 microprocessor includes? 40 19 27 21 None Hint 3). The 8085 microprocessor program counter or PC is a 16-bit register, for the reason that? At a time it calculates 16-bits Address lines are 16 It helps the user in storing 16-bit data for the time being At a time it has to obtain two 8-bit data None Hint 4). In 8085A Intel microprocessor, the signal of an ALE signal is finished high to...? Allow the data bus to be utilized like a low order address bus To handle D0-D7 data from the data bus To immobilize data bus To get all the above functions None Hint 5). Which of the following is the first machine cycle instruction for an 8085 Intel microprocessor. Write cycle for a memory Operation code for fetch cycle Read cycle for a memory Input/output read cycle None Hint 6). What is the function of the READY signal in an 8085 microprocessor? To specify to the user that 8085 is working properly as well as is ready for utilize To offer appropriate WAIT states as the 8085 is conversing by a slow peripheral device To slow down a quick device for communicating at the device of microprocessor None of these None Hint 7). Which of the following flag is present in the 8085 microprocessor? Sign flag Trap flag Parity flag Auxiliary carry flag None Hint 8). The ALU of 8085 microprocessor includes? Accumulator, short-term register, arithmetic & logic circuits Arithmetic, Accumulator, logic circuits & 5 flags Accumulator, short-term register, logic circuits, arithmetic, & 5 five flags Accumulator, arithmetic & logic circuits None Hint 9). Which of the following 16-bit register is for 8085? Accumulator Register C Stack pointer Register None Hint 10). What are the DMA signals for 8085 microprocessors? READY HOLD HLDA All of the above None Hint 11). What kind of interrupts are RST0 to RST7 in the 8085 microprocessor? Logical interrupts Hardware interrupts Conditional interrupts Software interrupts None Hint 12). Which of the following interrupt is non-vectored in 8085? RST 5.5 TRAP INTR RST 7 None Hint 13). The segments of 8085 microprocessor includes? 4 3 2 1 None Hint 14). Which of the following microprocessor includes virtual memory in the family of Intel microprocessors? Pentium 80386 80286 80486 None Hint 15). How many maskable interrupts are available in the 8085 microprocessor? 1 4 6 8 None Hint 16). Which of the following STACK is used in 8085? LIFO FIFO LILO FILO None Hint 17). How many bytes are present in the 8085 instruction 1 or 2 1, 2 or 3 Only 1 2 or 3 None Hint 18). The addressing technique which is not used in 8085? Register Relative Immediate Indirect Register None Hint 19). Which of the following register is not used in the 8085 programming model? Instruction Status Memory address Temporary Data None Hint 20). Consider the below registers like 1). Accumulator & flag register2). Registers B & C 3). Registers D &E 4). Registers H & LAnd which of the above registers can be coupled jointly for making a 16-bit register? 1, 3 & 4 1, 2 & 3 2, 3 & 4 1, 2 & 4 None Hint 21). The maskable interrupts in 8085 microprocessor are? 2 4 6 8 None Hint 22). Which of the following stack is used in 8085? LIFO FIFO LILO FILO None Hint 23). In the 8085 instruction set, how many bytes are present? 1 or 2 1 or 2 or 3 2 4 None Hint 24). In 8085, which of the following addressing method is not used? Immediate Relative Register indirect Register None Hint 25). Which of the below register is not used in the programming of 8085? Instruction Status Memory Address Temporary Data None Hint 8085 Microprocessor MCQs for Interviews 26). Data transfer in handshaking mode is called? Interrupt data-driven Synchronous Asynchronous DMA None Hint 27). Universal shift register operates……modes? 1 2 3 4 None Hint Please refer to this link to know more about Shift Registers 28). Which of the following instruction will affect the highest number of flags? DBR A RAL XRA A RBL None Hint 29). Which of the following instructions is used with the Direction flag? Stack String Branch Arithmetic None Hint 30). The 8085 consists of…..outputs? 15 18 27 30 None Hint 31). Which of the following register is 16-bit in 8085? Register A Accumulator Register C Stack Pointer None Hint 32). 8085 microprocessor is designed by? Intel Dell IBM VAX None Hint 33). In 8085 microprocessor, the address bus with 16-bit can address up to? 8 KB 16 KB 32 KB 64 KB None Hint 34). How many general-purpose registers are there in 8085? 2 4 5 6 None Hint 35). The data within the stack is known as? Pulling data Pushed data Pushing data Pulled data None Hint 36). The TRAP address in 8085 is? 002CH 0024H 0105H 013AH None Hint 37). The data transfer from…. to…. is not possible in a microprocessor? ACCU to memory Memory to ACCU ACCU to ACCU One memory to another memory None Hint 38). The term ‘EA’ in the microprocessor stands for? Enable address Efficient address Exclusive address Effective address None Hint 39). INTR stands for? Interrupt reset Interrupt response Interrupt request Interrupt ronaugh None Hint 40). The example of a microprocessor-based on accumulator? Motorola 6809 Intel 8085 Intel 8086 Motorola 6807 None Hint 41). Which of the following signal not comes under the control bus? Reset Enable Read Write None Hint 42). The technology used to design the first 8085 microprocessor is? TTL NMOS CMOS PMOS None Hint 43). The opcodes present in the 8085 microprocessor is…? 230 246 250 256 None Hint 44). In 8085, the possibilities of mapping for memory registers are…? 54536 61536 65536 55536 None Hint 45). The addressing mode used in the 8085 microprocessor for a list and array operations….? Immediate Indexed Direct Base register None Hint 46). In 8085, the software interrupt is.? INTR RST-5 TRAP RST-5.5 None Hint 47). The hardware interrupt in 8085 is.? INTR RST-5 EA HLDA None Hint 48). The address lines required to connect the microprocessor with a 4KB RAM is.? 10 12 20 25 None Hint 49). BCD addition in 8085 can be performed by…instruction? DAA LXI LDA LHLD None Hint 50). The two-word instruction in 8085 microprocessor is…? IN 01H JMP 2085H MOV A, B ADC 2500H None Hint 8085 Microprocessor MCQs for Exams 51). Which of the following includes within ‘n’ instruction Memory Address of the data Instruction operates Operation code None Hint 52). For which of the following flag, the conditional instructions are not dependent? AC C CY P None Hint 53). Which of the following chip is a DMA controller? 8237/57 8279 8253/54 8155 None Hint 54). PSW of 8085 has five flags they are? S, Z, AC, P, OV S, OV, Z, AC, P S, Z, AC, P, CY S, Z, OV, P, CY None Hint 55). In 8085 microprocessor, which of the below cycle is used to fetch & execute an instruction? Memory Instruction CLK Machine None Hint 56). BIU stands for? Bus interrupt unit Bus instruction unit Bus interface unit None None Hint 57). What is the full form of IP? Instruction Pair Instruction Power Instruction Pointer Instruction Purpose None Hint 58). What is CS in a microprocessor? Component Set Code Segment Counter Segment Component Segment None Hint 59). What is DS in a microprocessor? Declare Segment Data Segment Direct Segment Double Segment None Hint 60). When the Accumulator is wide with 16-bit then it is called? AH AX DX AL None Hint 61). What is PROM? Programmable Read-Only Memory Post-Random Only Memory Pre Read-Only Memory Programmable Random Only Memory None Hint 62). What is EPROM? Electrical Programmable ROM Erasable Programmable ROM Enable Programmable ROM Erasable Programmable Random Only Memory None Hint 63). Which of the following is used to locate the data item to store? Fetch Database String Enable None Hint 64). The computer ALU includes? Hard disks Registers Memory Counters None Hint 65). Which of the following ICs are used for processing the data? RAM ROM PROM Microcontrollers None Hint 66). An error within computer data is called? Halt Bug Mistake Inaccuracy None Hint 67). The word length in a 32-bit microprocessor is equivalent to….? 3 byte 4 byte 5 byte 6 byte None Hint 68). The access time of cache memory has….? Shortest Longest Middle None of the above None Hint 69). In computers, which of the following part is used to calculate & compare? ALU Disk Control Modem None Hint 70). In a computer, the word length can be measured in…..? Bits Bytes Memory RAM None Hint 71). Which of the following processor was invented by Intel? 8009 4004 8090 8805 None Hint 72). What is the SI stands for in a microprocessor? Source Index Source Interest Standard Index Segment Index None Hint 73). What is BP stands for? Base Pointer Bus Pointer Byte Pointer Bit Pointer None Hint 74). The buses connected in the 8085A microprocessor are? 2 3 5 7 None Hint Please refer to this link to know more about Microprocessor 75). Which of the following software is used to run a microprocessor? VHDL Assembly Language C Java None Hint 8085 Microprocessor MCQs for Quiz 76). Which of the following processor is programmed during the process of manufacturing? PROM EPROM MROM EEPROM None Hint 77). In a machine, the o/p of the assembler is called as? Object program CNC program Symbolic addressing Source program None Hint 78). Which of the following pair of the register is used to specify memory? H & L E & D B & C X & Z None Hint 79). The nonmaskable interrupt examples in 8086…? intr trap rst5.5 rst6.7 None Hint 80). Which of the following load pointer is used to load the stack pointer? bhs bgt LDS RTS None Hint 81). In a flag register of 8085, how many FFs are there? 3 5 7 10 None Hint 82). Which flag is used in BCD operations of 8085? AC Z S P None Hint 83). Which of the following addition is performed in DAA instruction of 8085? Binary BCD Octal Excess-3 None Hint 84). Which of the following instruction uses direct addressing? CMA STA RLC RRC None Hint 85). Which of the following circuit is used to send out two messages simultaneously within a single direction? Simplex Duplex Diplex Quadruplex None Hint 86). Which of the following is not a control bus signal? READ RST or RESET ENABLE HOLD None Hint 87). Which of the following memory is used to retries the instructions? Virtual Main Cache Control None Hint 88). The signal detached by the CPU to finish the operation of whole memory? Write Enable Read ALE None Hint 89). The 8085 uses ….frequency? 2 MHz 3 MHz 10 MHz 15 MHz None Hint 90). The 4-index register in the microprocessor is used for? Division Multiplication Subtraction Arithmetic None Hint 91). What is IP in a microprocessor? Internet Protocol Instruction Pointer Internet Pointer Interrupt Protocol None Hint 92). Which of the following is a typical dedicated register? PC IP SP LR None Hint 93). What is the function of a logical unit within the computer’s CPU? To evaluate numbers To generate result To control information flow None of the above None Hint 94). What is the function of a logical unit within the computer’s CPU? To evaluate numbers To generate result To control information flow None of the above None Hint 95). Which of the following ICs are called the Si chips? RAM PROM ROM EPROM None Hint 96). Which of the below ICs is not belongs to 8-bit? 8080 4004 8085 68000 None Hint 97). The speed of any microprocessor can be determined in terms of…….? Based on Time Frequency of CLK Resistance Bits/Sec None Hint 98). The direction of the data line is? Bidirectional Unidirectional Tri-directional Multidirectional None Hint 99). In which of the following RAM, Bipolar transistors are used? Static RAM Dynamic RAM DDR Permanent None Hint 100). Dynamic RAM is designed by…..? MOS transistors ICs BJTs FETs None Hint Time's up
