Digital Electronics Objectives Part 18

341 . 119 times program jump to the LOOP.

342 . The program can be changed to loop 210 times by changing first instruction to MVICD211.

343 . Interaction between a CPU and a peripheral device that takes place during an I/O operation is known as handshaking.

344 . Addressing in which the location of the data is contained within the mnemonic is knows as implied addressing.

345 . Addressing in which the instruction contains the address of the data to be operated on, is known as direct addressing.

346 . Match the following.
Column I Column II
(a) Pop (i) to save data in the stock
(b) Push (ii) to read data from the stack
(c) Stack (iii) a portion of memory reserved for return addresses and data
(d) Mask (iv) a byte used with an ANI instruction to blankout certain bits
a—(ii), b—(i), c—(iii), d—(iv)

347 . A floppy disc is a thin plastic disc coated with magnetic oxide.

348 . Interrupt-driven I/O is a type of I/O transfer that both hardware and software.

349 . Restart is special type of CALL in which the address is not programmed but built into the hardware.

350 . 8085 has 8 software restarts and 4 hardware restarts.

351 . Serial input data of 8085 can be loaded into bit 7 of the accumulator by executing a RIM instruction.

352 . In 8085, TRAP is used for catastrophic events like temporary power failure.

353 . The address to which a software or hardware restart branches is known as vector location.

354 . Vectored interrupt is an interrupt that takes the program to a vector location, TRAP vectors to 0024 H, RST 7.5 to 003 CH, RST 6.5 to 0034 H and RST 5.5 to 003 CH.

355 . In 8085 usually the vector location and the next two memory location contain a JMP instruction. This allows the program to branch to a longer sub-routine.

356 . TRAP is non-maskable where RST 7.5. RST 6.5, RST, 5.5 are maskable.

357 . In 8085, to disable the whole interrupt system(except TRAP) the DI instruction may be used.
Question 358 to 361 refer to data given below:

Suppose the accumulator contains CAH after the RIM is executed.

358 . Serial input data is high.

359 . 7.5 are pending interrupts.

360 . Interrupt-enable flag is high.