85.2.2. Instrukční sada

85.2.2. Instrukční sada
	85.2. CDC 160

85.2.2.1.
85.2.2.2. Podprogramy

Většina instrukcí má následující formát

Obrázek 85.3. Formát instrukcí počítače CDC-160

 11 10 09 08 07 06 05 04 03 02 01 00
 ___________________________________
|  |  |  |  |  |  |  |  |  |  |  |  |
|__|__|__|__|__|__|__|__|__|__|__|__|
|           |     |                 |
|   Opcode  | Mode|     Address     |
|                 |                 |
|     6-bit F     |     6-bit E     |

Tabulka 85.5. Tabulka instrukcí CDC-160

opcode	význam
0000	Immediate Instructions
0001	Immediate Instructions
0010	And
0011	Or
0100	Load
0101	Load Complement
0110	Add
0111	Subtract
1000	Store
1001	Shift and Replace
1010	Add and Replace
1011	Add One and Replace
1100
1101
1110
1111

Tabulka 85.6. Adresní módy CDC-160


00	Direct	Přímé adresování nulté stránky paměti. Tedy pamětových buněk na adresách 0 až 63.
01	Indirect
10	Forward Relative
11	Backward Relative

Tabulka 85.7.

Opcode	Mnemonic	Description
000 000 000 000	ERR	Halt	halt the cpu
000 000 000 ???	NOP
000 000 000 111	NOP
000 000 bbb vvv		bank set	b≠0
000 001 000 000	BLS
000 001 000 001	PTA	Transmit Program Counter to Accumulator	A ← P
000 001 000 010	LS1	Shift Left
000 001 000 011	LS2	Shift Left 2
000 001 000 100	CBC
000 001 000 101	ATE
000 001 000 110	ATX
000 001 000 111	ETA
000 001 001 000	LS3	Shift Left 3
000 001 001 001	LS6	Shift Left 6
000 001 001 010	MUT	Multiply by 10
000 001 001 011	MUH	Multiply by 100
000 001 001 100	RS1	ROR A
000 001 001 101	RS2	ROR A,2
000 001 010 000	CIL
000 001 011 000	CTA
000 001 100 xxx	SBU
000 001 101 xxx	STP
000 001 110 xxx	STE
0000 10		And immediate	A ← A & E
0000 11		Or immediate	A ← A \| E
0001 00		Load	A ← E
0001 01		Load Complement	A ←
0001 10		Add immediate	A ← A + E
0001 11		Subtract immediate	A ← A - E
110x 00		Zero Jump	if x=0 then dst=P+E else dst=P-E
110x 01		Non-Zero Jump	if x=0 then dst=P+E else dst=P-E
110x 10		Positive Jump	jump if A is positive
110x 11		Negative Jump	jump if A is negative
1110 00		Jump Indirect	P ← M[E]
1110 01		Jump Forward Indirect
1111 1111 1111		Error	halt the cpu, same as Halt

Addressing modes

No Address (n): E is used as the lower 6 bits of a 12-bit operand, the upper 6 bits being zeros. No storage reference is made.
Direct Address (d): E is used to address one of the first 64 storage locations from which a 12-bit operand is obtained.
Indirect Address (i): E is used to address one of the first 64 storage locations. The 12-bit contents of that location represent another address within storage. This latter address contains the 12-bit operand to be used by the instruction.
Relative Address Forward (f): E is added to the contents of P. The sum specifies a new address where the operand to be used by the current instruction will be found.
Relative Address Backward (b): E is subtracted from the contents of P. The resultant difference specifies a new address where the operand to be used by the current instruction will be found; this new address coannot be further than 63 locations from the current instruction. P is unchanged.
Relative Forward Indirect Address (fi): E is added to the contents of P in order to specify one of the 63 locations immediately following the current instruction address; the 12-bit contents of that location are used to address and operand anywhere on storage. P is unchanged.

Tabulka 85.8. Instruction table for CDC 160

mnemonic	opcode	name	addr mode	exec time	comments
ERR	00	Error		6.4	Stop operation
HLT	77	Halt		6.4	Stop operation
SHA	01	Shift A	(n)	6.4	Shift A depends on value E for its action. Three possibilities are: 0102 Shift the contents of A lef end-arround 1 binary position. 0110 Shift the contents of A left end-arround 3 binary positions. 0112 Multiply the contents of 1 by octal 12 (decimal 10).
LPN	02	Logical Product	(n)	6.4	Form in A the logical product of original contents of A and operand. A ← A && operand
LPD	10		(d)	12.8
LPI	11		(i)	19.2
LPF	12		(f)	12.8
LPB	13		(b)	12.8
LSN	03
LSD	14
LSI	15
LSF	16
LSB	17
OUT	73	Output	(fi)	12.8 + n*12.8	Transmit to selected output device words of information from storage beginning at starting address and continuing up to but not including the termination address.
OTN	74	Output Direct	(n)	6.4	Transmit lover 6 bits (E) of this instruction to selected output device. If more than 6 bits are used by output equipment other bits will be zero.
EXF	75	External Function	(f)	12.8	Transmit external function code to external equipment. The code is specified by contents of storage location E positions following external function instruction.
INA	76	Input to A	(n)	6.4	Read into A one frame of data from selected input device, clearing previous contents of A.


85.2.1. Registry		85.2.2.1.