1) Base of hexadecimal number system? Answer : 16 2) Universal gate in digital logic? Answer : NAND 3) Memory type that is non-volatile? Answer : ROM 4) Basic building block of digital circuits? Answer : Gate 5) Device used for data storage in sequential circuits? Answer : Flip-flop 6) Architecture with shared memory for instructions and data? Answer : von Neumann 7) The smallest unit of data in computing? Answer : Bit 8) Unit that performs arithmetic operations in a CPU? Answer : ALU 9) Memory faster than main memory but smaller in size? Answer : Cache 10) System cycle that includes fetch, decode, and execute? Answer : Instruction 11) Type of circuit where output depends on present input only? Answer : Combinational 12) The binary equivalent of decimal 10? Answer : 1010 13) Memory used for high-speed temporary storage in a CPU? Answer : Register 14) Method of representing negative numbers in binary? Answer : Two's complement 15) Gate that inverts its input signal? Answer : NOT 16)
Access Methods
Sequential Access
* A sequential access file copys magnetic tape operation, and generally supports a few operations:
• read next - read a record and advance the tape to the next place.
• write next - write a record and advance the tape to the next place.
• rewind
• skip n records - Might or might not be supported. N may be limited to positive
numbers, or may be limited to +/- 1.
Direct Access
* Jump to any record and read that record. Operations supported include:
• read n - read record number n. ( Note an argument is now needed. )
• write n - write record number n. ( Note an argument is now needed. )
• jump to record n - could be 0 or the endof file.
• Query current record - used to turn back to this record later.
• Sequential access can be easily copied using direct access. The inverse is complicated and inefficient.
Other Access Methods
An indexed access scheme can be easily construct on top of a direct access system. Very large files may need a multi-tiered indexing scheme, i.e. indexes of indexes.
