Sperva neskol'ko sokrashchenij:
UART Universal Asyncronous Receiver Transiver
CRC Cyclical Redundancy Check
LCD Luquid Cristal Display - ZHidkokristallicheskij displej
LED Light Emitting Diode - Svetodiod
DTE Data Terminal Equipment - Komp'yuter, terminal
DCE Data Communication Equipment - Modem
Kabeli: Modemnyj (pryamoj) - soedinyaet DTE s DCE (Host-modem)
Nul'-modemnyj(perevernutyj) - soedinyaet DTE s DTE (Host-Host)
Raspaj modemnogo kabelya.
Standartnaya PC imeet dva posledovatel'nyh porta RS-232C:
COM1 - 9 pin papa, COM2 - 25 pin papa. Vneshnij modem imeet pos-
ledovatel'nyj port 25 mama. Dlya podklyucheniya modema ispol'zuyut-
sya dva vida kabelej:
Host/DTE(9mama) >---> Modem/DCE(25papa)
Host/DTE(25mama) >---> Modem/DCE(25papa)
papa mama papa
123..5 DB-9 DB-25
67.9 54.321 123...13
mama papa 9876 14..25
DTE(Host) DCE(Modem)
DB9 DB25 | DB-25 Signal
---------+------------------------------------------
1 8 <--- 8 CD Carrier Detect "Modem: soedinen"
2 3 <--- 3 RxD Receive Data
3 2 ---> 2 TxD Transmit Data
4 20 ---> 20 DTR DTE Ready "Host: vklyuchen"
5 7 7 Signal ground
6 6 <--- 6 DSR Data Set Ready "Modem: vklyuchen"
7 4 ---> 4 RTS Request To Send "Host: ya gotov"
8 5 <--- 5 CTS Clear To Send "Modem: ya gotov"
9 22 <--- 22 RI Ring Indicator "Modem: nam zvonyat"
V sluchae kabelya 25 na 25 vse ustroeno ochen' prosto: vse signaly
idut napryamuyu - odin v odin.
1 7
2 20
3 2
4 3
5 8
6 22
7 5
8 4
9 6
Raspaj nul'-modemnogo kabelya.
Host/DTE(25mama) >---< Terminal/DCE(25mama)
Host/DTE(9mama) >---< Terminal/DCE(25mama)
Ideya 1: vse "simmetrichnye" signaly perekidyvaem krest-nakrest.
TXD-RXD, DTR-(DSR,CD), CTS-RTS, GND-GND
Ideya 2: Gotov/Gotov zamykaem na samom portu, i ekonomim provod.
Esli dostatochno obnaglet', to nam hvatit 3 provodov.
Esli dlina shnura prilichnaya (bol'she neskol'kih metrov),
nastoyatel'no rekomenduetsya ispol'zovat' 4 provoda - 2 vitye
pary, po odnomu zemlyanomu provodu v kazhdoj. Krome togo,
ekonomiya provodov privedet k tomu, chto ne budet rabotat' Hard-
ware Flow Control (DTR/DSR), pridetsya pol'zovat' Software
(XON/XOFF).
Fakticheski: 2 provoda TxD na RxD, i tretij - signal'naya zemlya.
Lokal'no, na samom portu zamykaem RTS-CTS, DSR-DTR i vse eto na
DCD/DTR.
Host Mama Mama Terminal
Signal DB9 DB25 | | DB25 DB9 Signal
-----+----+-----+----------+-----+-------------------
CD 1 8 <-+- - - - 20* 4 DTR
DSR 6 6 <-+ +-- 6 6 DSR
DTR 4 20 - - - -+-> 8 1 CD
GND 5 7 ========== 7 5 GND
RxD 2 3 <========= 2 3 TxD
TxD 3 2 =========> 3 2 RxD
RTS 7 4 ---------> 5 8 CTS
CTS 8 5 <--------- 4 7 RTS
RI 9* 22* 22* 9 RI
Primechanie: * Pin ne ispol'zuetsya;
--- Bez provoda vpolne mozhno obojtis'
esli ne nuzhen Hardware Flow Control;
- - Bez provoda tochno mozhno obojtis'.
Al'ternativnaya kartinka urezannogo nul'-modema
CD -<-+ +->- CD
DSR -<-* *->- DSR
DTR ->-+ +-<- DTR
GND ------------ GND
RXD ------<----- TXD
TXD ------>----- RXD
RTS ->-+ +-<- RTS
CTS -<-+ +->- CTS
Vidy konnektorov
RJ-11 4pin 2-h provodnoj kabel' dlya importnyh telefonov;
RJ-8 8pin 2-h ili 4-h provodnaya vydelennaya liniya;
RJ-45 8pin vitaya para(Ethernet twisted pair) i RS-232;
Raspaj nul'-printernogo kabelya "Laplink".
Raspaj kabelya pod PLIP sovpadaet s tem, chto ispol'zuetsya shiroko
izvestnymi kommunikacionnymi programmami pc-pc dlya MSDOS, i na-
zyvaetsya "Laplink". 25papa <---> 25papa
Pin Name Connect pin - pin
--------- -------------------------------
GROUND 25 - 25
D0 ->ERROR 2 - 15
ERROR ->D0 15 - 2
D1 ->SLCT 3 - 13
SLCT ->D1 13 - 3
D2 ->PAPOUT 4 - 12
PAPOUT ->D2 12 - 4
D3 ->ACK 5 - 10
ACK ->D3 10 - 5
D4 ->BUSY 6 - 11
BUSY ->D4 11 - 6
D5 7*
D6 8*
D7 9*
STROBE ? 1*
FEED ? 14*
INIT ? 16*
SLCTIN ? 17*
ZAMECHANIE: Piny, pomechennye "*" ne podklyuchat'.
Etxra grounds are 18,19,20,21,22,23, and 24.
If the cable you are using has a metallic shield, it should be
connected to the metallic DB-25 shell at one end only.
VNIMANIE: Govoryat, chto nepravil'no zapayannyj "Laplink" kabel'
mozhet "szhech'" printernyj port, i voobshche ves'
kontroller vvoda-vyvoda. Ne mozhet. Tam tol'ko obychnye
TTL ili CMOS vhody/vyhody, k tomu zhe s ogranichitelyami.
Hotya kabelya vse ravno payat' nado pravil'no.
Fizicheskij protokol RS-232/V.24 i signal Break
Sostoyaniya linii RS232:
mark = logical 1 = negative voltage between -3 and -12V
space = logical 0 = positive voltage between +3 and +12V
V normal'nom "holostom" sostoyanii na linii stoit "mark".
Normal'nyj asinhronnyj simvol sostoit iz:
Start bit (space)
7 or 8 data bits (marks or spaces)
an optional parity bit
1, 1.5 or 2 stop bits (mark)
BREAK opredelyaetsya kak dlitel'noe sostoyanie (space) zavedomo
prevoshodyashchee po dlitel'nosti lyuboj asinhronnyj simvol. (Obychno 125ms to
500ms).
Pri vklyuchenii/vyklyuchenii DTE, a tak zhe pri vydergivanii/vstavlenii
kabelya vozmozhen vsplesk napryazheniya, kotoryj budet vosprinyat kak BREAK
Bezgolovye Sun i vyklyuchenie konsolya
CHtoby vyzvat' boot-monitor s alfavitnogo konsolya, nazhmite
na nem klavishu BREAK ( Na terminale vt220 BREAK - eto klavisha
F5).
Vyklyuchat' alfavitno-cifrovoj konsol' na Sun-servere
nel'zya - pri etom terminal generit signal BREAK, i Sun
perehodit v ostanov v boot-monitore.
U etoj problemy sushchestvuet tri dovol'no krivyh resheniya opisannyh na
http://www.cisco.com/warp/public/770/fn-tsbreak.html
Zakazat' u Sun novyj draver, kotoryj umeet obrabatyvat' signal BREAK
Order a modified TTY driver from Sun that defeats the interpretation of
the BREAK signal. This driver allows you to re-map the BREAK character
to any custom setting, and does not prohibit the use of L1-A directly from the
master workstation keyboard. The driver part number from Sun is "CONSULT-ZSBRK".
Ustanovit' adapter consol'nogo porta ignoriruyushchij signal BREAK
A model NUD4273 "non-aborting serial console adapter" from NUData will prevent the
BREAK signal from ever reaching the console port. The devices cost about $89 USD each.
They can be purchaed through Micro Warehouse at http://www.warehouse.com.
"Soldering Iron" - postavit' rezistor na kabel' i likvidirovat' etim BREAK naproch'
If you tie a 4.7K resistor between pins 3 and 25 of the ttya port,
you electrically prevent a BREAK signal either from the key or from disconnecting
or powering down the terminal. This prevents intentional halts except by removing
the resistor, but does allow recabling.
Last-modified: Mon, 16 Sep 2002 12:40:44 GMT