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1 8086?
2 ³ .
3 Intel?
4 ( ).
5 ?
6 - ?
7 - ?
ѳ 16- 32- 680 0 Motorola , , . , , , , 䳿 䳿 . -. , .
̳ 680 0 Motorola Macintosh, ᒺ, VME. 68000, 68 0 0 ( Embedded Controller). , .
68000 16- 24- , 16 . 16,7 . 68000, n --㳺, 1,6 , 68 000, -㳺, 260 . 68 000 20 380 .
, , , 680 0, , , . :
;
.
. , .
S . S = 1, . S 0. ; () (RESET).
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68000, . 11.1, 32- , , .
³ D 7... D 0 .
³ 7... 0 , . 7 ( ´7) . ³ . , USP SSP. .
11.1 68000
. , 24- , 24 .
SR . . R, . . 11.2.
11.2 SR
() R , , .
:
C ( ) . = 1 ;
V ( ) V = 1 ;
Z ( ) , 0, 1;
N ( ) . N = 1 䒺 ;
( ) . .
SR :
( ) = 1;
S ( ) . S = 1 , S = 0 ;
2... 0 , .
SR .
̳ 68000 , , , , , - . ( ), . , 16 , , , 4. , , , 1 . . big-endian, little-endian, Intel. () () . 11.3. N .
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ϳ ² , . 11.4 ( ). . ϳ 24- ( 23... 0), , . 16- (D 15... D 0), . ( , ).
11.3 () ()
11.4 ² 68000
, . 11.4. # , 0 ( ).
CLK . .
:
RESET# . RESET# RESET . RESET# , . , S 1, . $000000 SSP, $000004 . SR, , , . RESET, .
HALT# . HALT# , , . HALT# . RESET#.
BERR# . , , , , . DTACK# .
:
AS# , ; .
R/W# /. . R/W#, 1, () ; , 0, , () .
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UDS# .
LDS# .
UDS#, LDS# . LDS# = 0 UDS# = 1 , LDS# = 0 UDS# = 0 .
DTACK# , .
, . ֳ , . :
BR# - . , , , , 23... A 0 D 15... D 0 , .
BG# . .
BGACK# . BG# . BR# .
ϳ BGACK 1 , .
, . . :
. , , (CLK). . AS# R/W# .
VPA# . , .
VMA# . VPA#. ϳ .
, . , FC 2... FC 0. ³ . 11.1.
11.1
FC 2 | FC 1 | FC 0 | |
, INTA# .
, , , ( ) , .
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, IRQ 1... IRQ 7, . ֳ IPL#. ³ IPL 2... IPL 0# . 11.2.
11.2
IPL 2... IPL 0 | ||
0 () | ||
IRQ 1 | ||
IRQ 2 | ||
IRQ 3 | ||
IRQ 4 | ||
IRQ 5 | ||
IRQ 6 | ||
7 () | IRQ 7 |
. (Exception) , , , , . . - , , , ( , 璺 ). : , , 0, . , .
:
RESET#;
BERR#;
;
DTACK# VPA#;
, ;
.
:
, RESET, TRAP, TRAPV, CHK;
;
0 ( DIVS, DIVU);
, ;
( = 1);
;
, 1010. - , ;
.
: , S = 1, SR . (Ve), . , , , (FC 2... FC 0), . , .
. $000...$3 FF. , 256 . Ne 0 255 Ae, Ve . 4 (Ae = 4 Ne). . г . 11.3.
RTE RTS. RTE , RTS .
Ne = 0 , RESET, , RESET#. $000 SSP, $004 . , Ve.
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11.3 г
Ne | Ae | |
$000 | ( SSP) | |
$004 | ( PC) | |
$008 | ||
$00 C | () | |
$010 | ||
$014 | ij 0 | |
$018 | CHK | |
$01 C | TRAPV | |
$020 | ||
$024 | ( = 1) | |
$028 | 1010 | |
$02 C | 1111 | |
12...14 | $030...$038 | |
$03C | ||
16...23 | $040...$05 E | |
$060 | ||
25...31 | $064...$07 C | |
32...47 | $080...$0 BF | TRAP Nt = 0...15 |
48...63 | $0C0...$0 FF | |
64...255 | $100...$3 FF |
Ne = 2 ( ) , () . , DTACK# . ϳ , , . , HALT#.
1010 1111 , 6800. , , , 1010, , , . 1111 . , 68000 , .
15 ( ) 24 ( ), .
TRAP Ne = 32 + Dt. , , .
(interruption) , , , . 7.2.2, ( ) ( ).
, , ( ), . ϳ . , , .
, , , . . . 11.2.
(I 2... 0) SR. (IRQ) . ³ . 11.4.
11.4
I 2... 0 | , | |
IRQ 1... IRQ 7 | ||
IRQ 1 (Li = 1) | IRQ 2... IRQ 7 | |
IRQ 2 (Li = 2) | IRQ 3... IRQ 7 | |
IRQ 3 (Li = 3) | IRQ 4... IRQ 7 | |
IRQ 4 (Li = 4) | IRQ 5... IRQ 7 | |
IRQ 5 (Li = 5) | IRQ 6... IRQ 7 | |
IRQ 6 (Li = 6) | IRQ 7 | |
IRQ 7 (Li = 7) | IRQ 7 |
. Li . 11.3 = $064...$07 C. - Ne. , , IVR, Ne, . , Ne = 15 ( ).
, , , IRQ#, , IPL 0... IPL 2, . 2... 0 SR, . FC 2... FC 0 111 (. 11.1), IACK#, , , , . . 11.5.
11.5
, IACK#, , VPA# . ϳ AV = $064...$07 C , .
, IACK#, D 7... D 0 Ne , DTACK#. , , AV = $100...$3 FF.
VPA# DTACK#, 24 .
68010 68851 (Memory Management Unit MMU).
MU 256 32 . , , . U . , , BERR#. , , , , . , , . , . BERR# -.
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1 68000 Intel?
2 68000?
3 , 68000?
4 68000?
5 68000?
6 68000 ?
7 ?
8 , ?
9 BERR# ?
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1 䳿 ?
2 68000?
3 ?