DMA, . DMA , . .
DMA : DRQx DACKx#, x . . 6.3 ( 8- ) ( 16-) DMA. .
1. DRQx DMA ( ).
2. IOR#, DACKx# MEMW#. , LA[23:17], ( ), BALE=H . DACKx# , x, a IOR# ( IOW#). IOR# ( IOW# ) , , DMA, AEN . , , .
3. 12 DRQx, . TC (Terminate Count), .
. 6.3. DMA
( ) , IOR# MEMR#, MEMW# IOW#. DMA.
DMA, , IOCHRDY ( 0WS# ). , DRQx, .
16- ISA 7 DMA: 8- ( 03) 16- (57), . 4 ( ). 8- 8- ( XT 3 0 ).
, . 12.4.
, 8- DMA 64 , ( , . . 12.3.2 12.5). 16- 64 , , . DMA , , 15 ( ).
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(bus mastering) - , DMA. , , , , , DMA ( ). , , . , - . ISA , 16- . , DMA - DMA ( 57). , , DRQx (x=57), DMA . , AEN ( ) DACKx. , MASTER#, DMA AEN . , , DRQx. ISA , ( ). 15 , (. ). ( ), , IOCHRDY, .
, , , , , (refresh) . , . 15 ( REFRESH#), DMA, . , ( . IBM PC. ). ISA DMA ( ). 15 REFRESH#, AEN=H BALE=H, MEMR#, SA[7:0] . DMA, REFRESH# , .
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- 15 , . 15 REFRESH#, . , , SA[7:0] MEMR#, AEN=0 BALE=1 . , , , , , , . , , , .
ISA . IRQ2-IRQ7 , IRQ9-IRQ15 . B4 (IRQ2/9) IRQ2 PX/XT. ( AT) IRQ9, ( 8-) IRQ2. IRQ9IRQ15 IRQ3IRQ7. (. . 12.4), / (IF) . . , . . . , - , , . , . . 12.4.
, ISA, , , , , ( ) .
IOCHK# (NMI), - . , , . NMI 3 (EIC) 061h, , NMI IOCHK#, 6 (IOCHK) .
PC/104
PC/104, , ISA. 104 , ISA. ISA PC/104 : , . MEMCS16#, IOCS16#, MASTER# 0WS# 20 , 4 .
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PC/104 . 6.4, . 6.5 6.6. PC/104 - . PC/104, . PC/104 ( ), (. 6.4, ). B10 C19 , ; . , . . 0,6" ( ). : J1 ISA-8, J2 ISA-16; (2,54 ), , 2,5 ( !). , , , D ( J2 , ).
. 6.4. PC/104: ,
6.5. J1/P1 PC-104
IOCHK# | 1 | GND |
SD7 | 2 | RESET |
SD6 | 3 | +5 |
SD5 | 4 | IRQ2/9 |
SD4 | 5 | 5 |
SD3 | 6 | DRQ2 |
SD2 | 7 | 12 |
SD1 | 8 | 0WS# |
SD0 | 9 | +12 |
IOCHRDY | 10 | |
AEN | 11 | SMEMW# |
SA19 | 12 | SMEMR# |
SA18 | 13 | IOWR# |
SA17 | 14 | IORD# |
SA16 | 15 | DACK3# |
SA15 | 16 | DRQ3 |
SAM | 17 | DACK1# |
SA13 | 18 | DRQ1 |
SA12 | 19 | REFRESH* |
SA11 | 20 | BCLK |
SA10 | 21 | IRQ7 |
SA9 | 22 | IRQ6 |
SA8 | 23 | IRQ5 |
SA7 | 24 | IRQ4 |
SA6 | 25 | IRQ3 |
SA5 | 26 | DACK2# |
SA4 | 27 | TC |
SA3 | 28 | BALE |
SA2 | 29 | +5 |
SA1 | 30 | OSC |
SA0 | 31 | GND |
GND | 32 | GND |
6.6. J2/P2 PC-104
C | D | |
GND | 0 | GND |
SBHE | 1 | MEMCS16# |
LA23 | 2 | IOCS16# |
LA22 | 3 | IRQ10 |
LA21 | 4 | IRQ11 |
LA20 | 5 | IRQ12 |
LA19 | 6 | IRQ15 |
LA18 | 7 | IRQ14 |
LA17 | 8 | DACK0# |
MEMR# | 9 | DRQ0 |
MEMW# | 10 | DACK5# |
SD8 | 11 | DRQ5 |
SD9 | 12 | DACK6# |
SD10 | 13 | DRQ6 |
SD11 | 14 | DACK7# |
SD12 | 15 | DRQ7 |
SD13 | 16 | +5 |
SD14 | 17 | MASTER# |
SD15 | 18 | GND |
19 | GND |
Pentium PCI, PC/104-Plus ( . 6.4). PCI 2 . PC/104 ISA, PCI ; -, (ISA, PCI) (PC) .