Registers/Modes/Records Flashcards
(22 cards)
0
Q
X
A
Mnemonic: Index Register
Use: addressing
#: 1
1
Q
A
A
Mnemonic: Accumulator
Use: arithmetic operations
#: 0
2
Q
L
A
Mnemonic: Linkage Register (J/RSUB) Use: stores the return address for jump subroutine #: 2
3
Q
PC
A
Mnemonic: Program Counter Use: stores the address of the next instruction #: 8
4
Q
SW
A
Mnemonic: Status Word Use: contains a variety of info (e.g. CC) #: 9
5
Q
B (XE)
A
Mnemonic: Base Register
Use:
#: 3
6
Q
S (XE)
A
Mnemonic: General Register
Use:
#: 4
7
Q
T (XE)
A
Mnemonic: General Register
Use:
#: 5
8
Q
F (XE)
A
Mnemonic: Floating Pt Accumulator
Use:
#: 6
9
Q
Format 0
A
Instruction Format Length (bytes): 3 Struct (bits) OP: 8 x : 1 Disp: 15
10
Q
Format 1
A
Instruction Format
Length (bytes): 1
Struct (bits)
OP: 8
11
Q
Format 2
A
Instruction Format Length (bytes): 2 Struct (bits) OP: 8 R1: 4 R2: 4
12
Q
Format 3
A
Instruction Format Length (bytes): 3 Struct (bits) OP: 6 nixbpe Disp: 12
13
Q
Format 4
A
Instruction Format Length (bytes): 4 Struct (bits) OP: 6 nixbpe Disp: 20
14
Q
iNdirect Addressing
A
N: 1 I: 0
Struct: op @m
15
Q
Immediate Addressing
A
N: 0 I: 1
Struct: op #c
16
Q
indeX Addressing
A
X:1
Struct: op m,x
17
Q
Base-relative Addressing
A
B:1 P:0
Struct: op m
18
Q
PC-relative Addressing
A
B: 0 P: 1
Struct: op m
19
Q
Extended Addressing
A
E: 1
Sruct: +op m
20
Q
Header Record
A
H
Word: prog name
Word: start addr
word: length(bytes)
21
Q
Text Record
A
T
Word: start addr
Byte: length(bytes)
Word10: obj code
