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Rst restart – Zilog Z80380 User Manual

Page 192

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Z380

U

SER

'

S

M

ANUAL

DC-8297-03

Z

ILOG

RST
RESTART

RST address

Operation:

if (XM) then begin

SP

SP - 4

(SP)

PC(7-0)

(SP+1)

PC(15-8)

(SP+2)

PC(23-16)

(SP+3)

PC(31-24)

end

else begin

SP

SP - 2

(SP)

PC(7-0)

(SP+1)

PC(15-8)

end

PC

address

The current Program Counter (PC) is pushed onto the stack and the PC is loaded with a
constant address encoded in the instruction. Execution then begins at this address. The
restart instruction allows for a call to one of eight fixed locations as shown in the table below.
The table also indicates the encoding of the address used in the instruction encoding. (The
address is in hexadecimal, the encoding in binary.)

Address

t encoding

00000000h

000

00000008h

001

00000010h

010

00000018h

011

00000020h

100

00000028h

101

00000030h

110

00000038h

111

Flags:

S:

Unaffected

Z:

Unaffected

H:

Unaffected

V:

Unaffected

N:

Unaffected

C:

Unaffected

Addressing

Execute

Mode

Syntax

Instruction Format

Time

Note

RST address

11-t-111

4+w

X

Field Encodings:

000 for 00h, 001 for 08h, 010 for 10h, 011 for 18h,
100 for 20h, 101 for 28h, 110 for 30h, 111 for 38h