Apple Talk-. Apple Talk Apple Computer Macintosh. Apple Talk -, Ethernet. Apple Local Talk, HDLC- 230,4 /.
Apple Talk 860 HDLC-- , SCC- Local Talk, , , ABORT- HDLC-. , Apple Talk HDLC- . Apple Talk- , APPLE. HDLC-koh- FMO- Local Talk Bus. HDLC- Apple Talk , . Apple Talk . 5.141.
3 ( 6 ), , , 1, IDLE. IDLE- c -
, .
, Apple Talk / 6 (preamble) 16 (postamble). 6- CD-.
HDLC- HDLC-. - HDLC-. 600 . 16- , . HDLC- 8- . 01111110 HDLC. Local Talk , 12-18 ( 16) . HDLC- ABORT-. .
, v , HDLC- Apple Talk.
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, , CRC. . , .
Local Talk HDLC, . HDLC- , . Local Talk- . 0x01 0x7F, . 0x80 0xFF, . Local Talk 4 :
1) ENQ (enquiry);
2) (ENQ acknowledgment);
3) RTS (request to send data frame);
4) CTS (clear to send data frame).
. . , RTS, . - , CTS . . . , , , . 200 (IFG-interframe gap). IFG = 50 . IDG (interdialog gap) 400 .
.
RTS ENQ-. , .
ENQ . OSI.
ENQ . OSI.
FM0. 1 , 0 - : , - . . . FM0 . SYNC- Local Talk .
, .
Apple Talk , RS-422 (transceiver). RS-422 SCC-; TxD, RxD rts, . rts Apple Talk RS-422 . Apple Talk . 5.142.
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3,686 , BRG-.
oversampling Apple Talk 16 . , Apple Talk HDLC-koh-, . GSMR PSMR Apple Talk.
. 5.142. Apple Talk
GSMR PSMR AppleTalk:
1. GSMR[MODE]:= 0010 - Apple Talk.
2. GSMR[ENR]:= 1 GSMR[ENT]:= 1 -
.
3. GSMR[DIAG]:= 00 - SCC-
4. GSMR[RDCR]:= 10 GSMR[TDCR]:= 10-
16 .
5. GSMR[RENC]:= 010 GSMR[TENC]:= 010 - / FM0.
6. GSMR[TEND]:= 0 - TxD FM0-
. TxD 1
.
7. GSMR[TRR]:= 11 - - 1.
8. GSMR[TPL] 000,
reamble-, 001, Apple Talk
6- ..
9. GSMR[TINV] = GSMR[RINV]:= 0 - FM0 .
10. GSMRfTSNC]:= 10 - RxD
1,5 16 .
, -
RxD-. Apple Talk
, CD- 6- -
.
11. GSMR[EDGE]:= 00 - DPLL
, .
12. GSMR [RTSM]:= 0 -
( = 1) ( = 0) . IDLE-, TEND. RTSM = 1, SCC- , IDLE.
HDLC- , .
PSMR , HDLC-:
1. PSMR[NOF]:= 0001 - : -
, -.
2. PSMR[CRC]:= 00 - 16- CRC-CCITT
.
3. PSMR[DRT]:= 1 - ,
= 0.
PSMR 0, .
BISYNC-. BISYNC-- ( -) , IBM 1960- . - , , , , , , , .
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BISYNC- ( - nontransparent transparent) NMSI IDL, GCI, .
: Transparent - , Transparent with header - Non Transparent without header- (. 5.143). 8- SYN1 SYN2, , 16- . .
8- , 16- CRC16. 7- , (VRC parity) (LRC).
SOH (Start of Heading) . , , .
(STX) (). -, . . . 8- DLE (Data Link Escape), , DLE , . DLE , DLE-. DLE- ( byte-stuffing). DLE BDLE BISYNC- (. 5.144).
BISYNC- (underrun) FIFO , , SYNC DLE-SYNC , . . , underrun DLE- .
DLE- V= 1 BDLE , BSC. SYNC, . - DLE, BSC. DLE, SYNC, . , , DLE-. DLE:= 1 . V = 0, .
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SYNC BSYNC (. . 5.144). (nontransparent) FIFO underrun, SYNC-, .
( hunt) BSYNC V = 1, SYNC- . V = 0, SYNC- .
BISYNC MODE GSMRJ-, BISYNC- PSMR (. 5.145).
, RXD TXD , , , DRT:= 1 PSMR, , .
RVD . , LSB-, . , MSB-, .
BISYNC- 860 . 5.84.
. ENT:= 1, BISYNC- , . RTSM GSMRH . RTSM=1, SYN1 SYN2, DSR. RTSM = 0, IDLE- ( 1).
, , . SYN1 SYN2 . NOS PSMR , . SYN1-SYN2 ([NOS3-NOS0J+1).
, R:= 0 L . L = 1 = 1, CRC16 LRC . . . L = 0, . . , .
, underrun, BISYNC- SYN1-SYN2 IDLE-. , DLE-SYNC.
, 1 = 1, , .
CRC PSMR , . CRC = 01, 8- 16- ^16+^15+^12+1. CRC = 11, 7- LRC VRC ( ). LRC Ȼ XOR 7- . VRC ( parity-) /, PSMR (. 5.85).
5.85
. = 1, . = 0, . BR = 1, BISYNC- BCS. , , STB STX. BR = 0, BCS .
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BISYNC- , DLE- DLE-, DLE-.
BISYNC- RESTART TRANSMIT, STOP TRANSMIT, GRACEFUL STOP TRANSMIT, INIT TX PARAMETERS.
cts. underrun , RISC- FIFO . , , UN:= 1 := 1 , . RESTART TRANSMIT. underrun DLE-XXX .
860 FIFO
32 SCC1 16 - SCC- ( TFL = 0
GSMR_H).
cts , CTS (CTS= 1). , , := 1 := 1 , . RESTART TRANSMIT.
. BISYNC- : BCS (CRC16 LRC, VRC), SYNC , DLE-SYNC DLE- DLE-DLE , .
( ENR = 1) - (hunt mode). 3YN1-SYN2, DSR. - , .
hunt ENTER HUNT MODE, , .
RTR . RTR = 0, SYNC- . RTR = 1, ( CRC16).
CR . RCLK BCS. RBCS = 0 PSMR, BCS. RBCS = 1, .
LRC , RPM / (. 5.86) .
5.86
, := 0, I = 1, . , , RxBD, = 1, .
BCS, BISYNC- . , L = 1, := 0. , , .
BISYNC- INIT RX PARAMETERS, ENTER HUNT MODE, CLOSE RX BD, RESET BCS CALCULATION. RESET BCS CALCULATION , , STX SOH, .
, ,
overrun , RISC- FIFO , BISYNC- , . , , OV:= 1 RX:= 1 , .
860 FIFO -
8 ( RFW = 1 GSMRH).
FIFO 8 SCC1 4 SCC-
.
CD , (CD = 1). , , CD:=1 RX:= 1 BISYNC-, . , .
BISYNC- /. (parity), , , , PR:= 1 RX:= 1 , / PAREC BISYNC-.
(hunt mode).
BISYNC- , RCLK CR . , , CRC CRC, . , CRC- , , CR:= 1 RX:= 1 , .
. BISYNC-. , , , . , , .
, . , , , , . , . , , - , BCS. ENQ , , BCS. . RCH BISYNC- , - . . , DLE-STX, , RTR:= 1 BISYNC-. DLE-ETX. SOH, RESET BCS CALCULATION, RCH .
BISYNC- , , . - BCS, .
ENQ . , ORC- .
RCH BISYNC- , .
, - . , 1 , , . .
BISYNC- CHAR1-CHAR8 (. 5.146) . CHAR1-CHAR8 . = 1 (end of table) . . = 0, . = 1, , 1 LRC, 2 CRC. . (End of Text) (End of Transmission Block) = 1. .
BISYNC- . = 0, . = 1, (hunt mode). - = = 1, BCS.
860 RCCM (. 5.147) BISYNC-.
() . i, , / CHAR . i, , 0- 2- , npi .
(. 5.87).
(. 5.87).
5.87
- HDLC BISYNC. . 5.88 , - BISYNC - HDLC.
5.88
HDLC BISYNC , . , , , .
, , - .
- , , , . BISYNC , , HDLC , , . , , , . P/F, . := 1 ( - Poll), , = 1. (1) F ( - Final). .
HDLC , , , BISYNC .
HDLC , . BISYNC - .
HDLC , -, , , -, , - , . HDLC , ( ), 8, . . , , . .
DDCMP. - DDCMP- (Digital Data Communication Message Protocol) DEC . DDCMP , - . - . 68302, 860 Motorola , .
DDCMP - - . - : , , . DDCMP- -, --, . . . DDCMP- , , .
. SYN1 SYN2, DSR DSYN1, 16- . ( ) . , ( SOH/ ENQ/DLE ADDR) -CRC1 CRC2. . 5.148.
SYN1-SYN2 iDLE-. 8- , . . :
1) (data message) SOH ( 0x81);
2) (control message)
ENQ ( 0x05);
3) (transparent message)
DLE ( 0x90).
-. COUNT. COUNT+F(Flag) 2 .
F (Flag) 2 , - corf.. :
bit 0 - (QSYNC ), , , ; ;
bit 1 - ( SELECT); ;
; multipoint-
.
DDCMP , FILL 0.
, , HDLC-. 8- NUM, - 8- RESP.
Message type - (. 5.89).
- (Acknowledge Message) , RESP. ACKTYPE - 1, ACKSUB - 0, F - , FILL - 0.
NAK- (Negative Acknowledge Message) , . REASON. NAK : RESP RESP+1 . NAKTYPE - NAK 2, REASON - , F - , FILL - 0.
REP- (Reply to Message Number) , NUM . , master- . REP- - NAK- , slave- () , master- (). REPTYPE - REP 3, REPSUB- REP 0, F- , FILL - 0.
(STRT - Start Message) , . STACK. . STRTTYPE - STRT 6, STRTSUB - STRT 0, F - ( 1), FILL - 0.
, (STACK - Start Acknowledge Message) STRT-, - . STCKTYPE - STACK 7, STCKSUB - STACK 0, F - ( 1), FILL - 0.
DDCMP :
1) on-line (), ;
2) off-line (), .
on-line. Off-line (), , / , (Transparent Message).