Test #4 Flashcards
Our Basic Computer has five types of machine instructions
False
The program counter (PC) register in our Basic Computer is 16 bits in length and hold the address of the next instruction to be executed
False
Which of the following are registers in the Basic Computer? Select all that apply
AC
BC
IR
AR
DR
AC
IR
AR
DR
Which of the following are addressing modes on the Basic Computer? Select all that apply
Alternative
Direct
Linked
Indirect
Batch
Direct
Indirect
Recursive subroutines are supported on the Basic Computer
False
Which machine instruction on our Basic Computer is used for branching to a subroutine?
BUN
ISZ
LDA
CLA
BSA
BSA
When a key on the keyboard of our Basic Computer is pressed, an interrupt cycle will always take place.
False
When an interrupt cycle occurs, where is the return address stored?
Word 1
PC
AR
Word 0
Word 1
Word 0
For register-reference instructions, the I bit (bit 15) of the instruction specifies the type of addressing that is being used
False
The timing signals T0, T1, T2, … in our Basic Computer are generated using which of the following? Select all that apply
8x1 multiplexer
4-bit sequence counter
1x8 demultiplexer
4 bit adder
4x16 decoder
4-bit sequence counter
4x16 decoder
Our Basic Computer has a 12-bit data bus that allows for transfer of data from one register to another
False
To perform a memory read/write operation on our Basic Computer, the address of the memory word involved must be placed in the Data Register
False
Which of the following are True concerning the I/O process on our Basic Computer? Select all that apply
FGO must = 1 for INPR contents to be transferred to AC
FGI must = 0 for keystroke to be transferred to INPR
The data transfer from OUTR to printer is serial
Flags FGI and FGO determine when data can be transferred
I/O must be done under program control
FGI must = 0 for keystroke to be transferred to INPR
The data transfer from OUTR to printer is serial
Flags FGI and FGO determine when data can be transferred
Execution of a machine instruction on our Basic Computer always begins at timing pulse T4
False
Suppose the “BSA $156” instruction is found in memory of our Basic Computer at memory location $03F. Assume this instruction has just executed. What value was stored in memory location $156 during the execution of this instruction?
$03F
$156
$160
$040
$050
$040
Our Basic Computer has over 40 different machine instructions
False
Suppose you want to create a counted loop in the machine language of our Basic Computer. What machine instruction is used to help create this loop?
BSA
LDA
CIR
ISZ
INP
ISZ
Suppose you want to create a counted loop that loops 5 times in the machine language of our Basic Computer. This requires a counter to be set up in a memory location. What should the value of the counter be?
5
10
12
-10
-5
-5
The following two microoperations can be done simultaneously on our Basic Computer:
AC <- DR, DR <- AC
True
The following operation can be done as a single microoperation on our Basic Computer:
PC <- AR + 1
False
The instruction $8500 in our Basic Computer specifies an ADD instruction using indirect addressing
False
Which of the following statement must be TRUE for the Interrupt Cycle to occur on our Basic Computer?
IEN must be set to 1
FGI or FGO (or both) must be 1
INPR must be 1
R must be 1
OUTR must be 1
IEN must be set to 1
FGI or FGO (or both) must be 1
R must be 1
When the Interrupt Cycle occurs on our Basic Computer, the return address is stored in the special memory location $100
False
At each timing pulse T0, our Basic Computer enters either the Fetch Cycle or the Interrupt Cycle
True
