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Commit | Line | Data |
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fd6b7a7f KZ |
1 | 25/10/95 Peter Orbaek <poe@daimi.aau.dk> |
2 | ||
3 | Some notes for using agetty with modems | |
4 | ||
5 | Using a comms program to initialize the modem | |
6 | --------------------------------------------- | |
7 | ||
8 | * Use kermit or minicom to initialize the modem to | |
9 | ||
10 | - be entirely quiet. | |
11 | - don't do local echo in command mode. | |
12 | - turn on DCD (carrier detect) only when there is a connection going. | |
13 | - enable auto-answer. | |
14 | - keep a constant computer/modem bitrate at all times. | |
15 | - optionally save this setup as the modem startup configuration. | |
16 | ||
17 | * Run agetty on the appropriate ttySn port with the arguments: | |
18 | * -w to wait for a CR or LF before writing the /etc/issue message | |
19 | * computer/modem bitrate | |
20 | * the tty name. | |
21 | ||
22 | Example from my modem setup, an old 2400 bps SupraModem using Hayes standard | |
23 | AT commands. | |
24 | ||
25 | Initialize modem using kermit with the commands | |
26 | ||
27 | AT E0 Q1 &D2 &C1 S0=1 &W0 | |
28 | ||
29 | to | |
30 | - turn off local echo from modem when in command mode (E0). | |
31 | - disable all result codes from modem (Q1). | |
32 | - make an on/off transition on the DTR line make the modem | |
33 | disconnect and go into command mode (&D2). | |
34 | - make the computer/modem DCD line track the modem/modem | |
35 | carrier detect signal, i.e. no connection means no | |
36 | carrier detect signal to the computer (&C1). | |
37 | - enable auto-answer after the first ring (S0=1). | |
38 | - store the configuration as the start configuration (&W0). | |
39 | ||
40 | The commands on your modem to achieve the same setup may vary, especially | |
41 | the &D2 and &C1 commands may not be entirely standard. | |
42 | ||
43 | Exit kermit/minicom. | |
44 | ||
45 | Put the command | |
46 | ||
47 | /sbin/agetty -w 2400 ttyS1 | |
48 | ||
49 | in the command field of the appropriate line in /etc/inittab to start | |
50 | agetty on /dev/ttyS1 with a 2400 bps speed between modem and computer. | |
51 | ||
52 | Initializing the modem with agetty | |
53 | ---------------------------------- | |
54 | ||
55 | Use the agetty -I command line option to specify a modem init string, like | |
56 | for the same setup as above, use the following agetty command in your | |
57 | /etc/inittab. | |
58 | ||
59 | /sbin/agetty -w -I 'ATE0Q1&D2&C1S0=1\015' 2400 ttyS1 | |
60 | ||
61 | The final \015 is an octal coding of the carriage return character | |
62 | ending the command string. | |
63 | ||
64 | If you're using simpleinit (part of this package) instead of the SYSV | |
65 | compatible init (you're most likely using the SYSV one!) then you must | |
66 | remove the single quotes from the command line above. | |
67 | ||
68 | Note that the &W0 command was not used here since the modem will be | |
69 | initialized each time agetty starts. | |
70 | ||
71 | With a V.34 (28.8 kbps) modem try starting with a command like: | |
72 | ||
73 | /sbin/agetty -w -I 'ATE0Q1&D2&C1S0=1\015' 115200 ttyS1 | |
74 | ||
75 | Note that agetty supports the higher (>9600 bps) serial speeds | |
76 | directly, there's no need to use setserial to use the higher speeds. |