1README for the ISDN-subsystem
2
31. Preface
4
5  1.1 Introduction
6
7  This README describes how to set up and how to use the different parts
8  of the ISDN-subsystem.
9
10  For using the ISDN-subsystem, some additional userlevel programs are
11  necessary. Those programs and some contributed utilities are available
12  at
13
14   ftp.isdn4linux.de
15
16   /pub/isdn4linux/isdn4k-utils-<VersionNumber>.tar.gz
17
18
19  We also have set up a mailing-list:
20
21   The isdn4linux-project originates in Germany, and therefore by historical
22   reasons, the mailing-list's primary language is german. However mails
23   written in english have been welcome all the time.
24
25   to subscribe: write a email to majordomo@listserv.isdn4linux.de,
26   Subject irrelevant, in the message body:
27   subscribe isdn4linux <your_email_address>
28
29   To write to the mailing-list, write to isdn4linux@listserv.isdn4linux.de
30
31   This mailinglist is bidirectionally gated to the newsgroup
32
33     de.alt.comm.isdn4linux
34
35  There is also a well maintained FAQ in English available at
36     http://www.mhessler.de/i4lfaq/
37  It can be viewed online, or downloaded in sgml/text/html format.
38  The FAQ can also be viewed online at
39     http://www.isdn4linux.de/faq/
40  or downloaded from
41     ftp://ftp.isdn4linux.de/pub/isdn4linux/FAQ/
42
43  1.1 Technical details
44
45  In the following Text, the terms MSN and EAZ are used.
46
47  MSN is the abbreviation for (M)ultiple(S)ubscriber(N)umber, and applies
48  to Euro(EDSS1)-type lines. Usually it is simply the phone number.
49
50  EAZ is the abbreviation of (E)ndgeraete(A)uswahl(Z)iffer and
51  applies to German 1TR6-type lines. This is a one-digit string,
52  simply appended to the base phone number
53
54  The internal handling is nearly identical, so replace the appropriate
55  term to that one, which applies to your local ISDN-environment.
56
57  When the link-level-module isdn.o is loaded, it supports up to 16
58  low-level-modules with up to 64 channels. (The number 64 is arbitrarily
59  chosen and can be configured at compile-time --ISDN_MAX in isdn.h).
60  A low-level-driver can register itself through an interface (which is
61  defined in isdnif.h) and gets assigned a slot.
62  The following char-devices are made available for each channel:
63
64  A raw-control-device with the following functions:
65     write: raw D-channel-messages (format: depends on driver).
66     read:  raw D-channel-messages (format: depends on driver).
67     ioctl: depends on driver, i.e. for the ICN-driver, the base-address of
68            the ports and the shared memory on the card can be set and read
69            also the boot-code and the protocol software can be loaded into
70            the card.
71
72   O N L Y !!!  for debugging (no locking against other devices):
73   One raw-data-device with the following functions:
74     write: data to B-channel.
75     read:  data from B-channel.
76
77   In addition the following devices are made available:
78
79   128 tty-devices (64 cuix and 64 ttyIx) with integrated modem-emulator:
80   The functionality is almost the same as that of a serial device
81   (the line-discs are handled by the kernel), which lets you run
82   SLIP, CSLIP and asynchronous PPP through the devices. We have tested
83   Seyon, minicom, CSLIP (uri-dip) PPP, mgetty, XCept and Hylafax. 
84
85   The modem-emulation supports the following:
86           1.3.1 Commands:
87
88               ATA      Answer incoming call.
89               ATD<No.> Dial, the number may contain:
90                        [0-9] and [,#.*WPT-S]
91                        the latter are ignored until 'S'.
92                        The 'S' must precede the number, if
93                        the line is a SPV (German 1TR6).
94               ATE0     Echo off.
95               ATE1     Echo on (default).
96               ATH      Hang-up.
97               ATH1     Off hook (ignored).
98               ATH0     Hang-up.
99               ATI      Return "ISDN for Linux...".
100               ATI0        "
101               ATI1        "
102               ATI2     Report of last connection.
103               ATO      On line (data mode).
104               ATQ0     Enable result codes (default).
105               ATQ1     Disable result codes (default).
106               ATSx=y   Set register x to y.
107               ATSx?    Show contents of register x.
108               ATV0     Numeric responses.
109               ATV1     English responses (default).
110               ATZ      Load registers and EAZ/MSN from Profile.
111               AT&Bx    Set Send-Packet-size to x (max. 4000)
112                        The real packet-size may be limited by the
113                        low-level-driver used. e.g. the HiSax-Module-
114                        limit is 2000. You will get NO Error-Message,
115                        if you set it to higher values, because at the
116                        time of giving this command the corresponding
117                        driver may not be selected (see "Automatic
118                        Assignment") however the size of outgoing packets
119                        will be limited correctly.
120               AT&D0    Ignore DTR
121               AT&D2    DTR-low-edge: Hang up and return to
122                        command mode (default).
123               AT&D3    Same as AT&D2 but also resets all registers.
124               AT&Ex    Set the EAZ/MSN for this channel to x.
125               AT&F     Reset all registers and profile to "factory-defaults"
126               AT&Lx    Set list of phone numbers to listen on.  x is a
127                        list of wildcard patterns separated by semicolon.
128                        If this is set, it has precedence over the MSN set
129                        by AT&E.
130               AT&Rx    Select V.110 bitrate adaption.
131                        This command enables V.110 protocol with 9600 baud
132                        (x=9600), 19200 baud (x=19200) or 38400 baud
133                        (x=38400). A value of x=0 disables V.110 switching
134                        back to default X.75. This command sets the following
135                        Registers:
136                          Reg 14 (Layer-2 protocol):
137                            x = 0:     0
138                            x = 9600:  7
139                            x = 19200: 8
140                            x = 38400: 9
141                          Reg 18.2 = 1
142                          Reg 19 (Additional Service Indicator):
143                            x = 0:       0
144                            x = 9600:  197
145                            x = 19200: 199
146                            x = 38400: 198
147                          Note on value in Reg 19:
148                            There is _NO_ common convention for 38400 baud.
149                            The value 198 is chosen arbitrarily. Users
150                            _MUST_ negotiate this value before establishing
151                            a connection.
152               AT&Sx    Set window-size (x = 1..8) (not yet implemented)
153               AT&V     Show all settings.
154               AT&W0    Write registers and EAZ/MSN to profile. See also
155                        iprofd (5.c in this README).
156               AT&X0    BTX-mode and T.70-mode off (default)
157               AT&X1    BTX-mode on. (S13.1=1, S13.5=0 S14=0, S16=7, S18=7, S19=0)
158               AT&X2    T.70-mode on. (S13.1=1, S13.5=1, S14=0, S16=7, S18=7, S19=0)
159               AT+Rx    Resume a suspended call with CallID x (x = 1,2,3...)
160               AT+Sx    Suspend a call with CallID x (x = 1,2,3...)
161
162           For voice-mode commands refer to README.audio
163
164           1.3.2 Escape sequence:
165               During a connection, the emulation reacts just like
166               a normal modem to the escape sequence <DELAY>+++<DELAY>.
167               (The escape character - default '+' - can be set in the
168               register 2).
169               The DELAY must at least be 1.5 seconds long and delay
170               between the escape characters must not exceed 0.5 seconds.
171
172           1.3.3 Registers:
173
174              Nr.  Default  Description
175              0    0        Answer on ring number.
176                            (no auto-answer if S0=0).
177              1    0        Count of rings.
178              2    43       Escape character.
179                            (a value >= 128 disables the escape sequence).
180              3    13       Carriage return character (ASCII).
181              4    10       Line feed character (ASCII).
182              5    8        Backspace character (ASCII).
183              6    3        Delay in seconds before dialing.
184              7    60       Wait for carrier.
185              8    2        Pause time for comma (ignored)
186              9    6        Carrier detect time (ignored)
187             10    7        Carrier loss to disconnect time (ignored).
188             11    70       Touch tone timing (ignored).
189             12    69       Bit coded register:
190                            Bit 0:    0 = Suppress response messages.
191                                      1 = Show response messages.
192                            Bit 1:    0 = English response messages.
193                                      1 = Numeric response messages.
194                            Bit 2:    0 = Echo off.
195                                      1 = Echo on.
196                            Bit 3     0 = DCD always on.
197                                      1 = DCD follows carrier.
198                            Bit 4     0 = CTS follows RTS
199                                      1 = Ignore RTS, CTS always on.
200                            Bit 5     0 = return to command mode on DTR low.
201                                      1 = Same as 0 but also resets all
202                                          registers.
203                                      See also register 13, bit 2
204                            Bit 6     0 = DSR always on.
205                                      1 = DSR only on if channel is available.
206                            Bit 7     0 = Cisco-PPP-flag-hack off (default).
207                                      1 = Cisco-PPP-flag-hack on.
208             13   0         Bit coded register:
209                            Bit 0:    0 = Use delayed tty-send-algorithm
210                                      1 = Direct tty-send.
211                            Bit 1:    0 = T.70 protocol (Only for BTX!) off
212                                      1 = T.70 protocol (Only for BTX!) on
213                            Bit 2:    0 = Don't hangup on DTR low.
214                                      1 = Hangup on DTR low.
215                            Bit 3:    0 = Standard response messages
216                                      1 = Extended response messages
217                            Bit 4:    0 = CALLER NUMBER before every RING.
218                                      1 = CALLER NUMBER after first RING.
219                            Bit 5:    0 = T.70 extended protocol off
220                                      1 = T.70 extended protocol on
221                            Bit 6:    0 = Special RUNG Message off
222                                      1 = Special RUNG Message on
223                                          "RUNG" is delivered on a ttyI, if
224                                          an incoming call happened (RING) and
225                                          the remote party hung up before any
226                                          local ATA was given.
227			    Bit 7:    0 = Don't show display messages from net
228                                      1 = Show display messages from net
229				          (S12 Bit 1 must be 0 too)      
230             14   0         Layer-2 protocol:
231                                      0 = X75/LAPB with I-frames
232                                      1 = X75/LAPB with UI-frames
233                                      2 = X75/LAPB with BUI-frames
234                                      3 = HDLC
235                                      4 = Transparent (audio)
236                                      7 = V.110, 9600 baud
237                                      8 = V.110, 19200 baud
238                                      9 = V.110, 38400 baud
239                                     10 = Analog Modem (only if hardware supports this)
240                                     11 = Fax G3 (only if hardware supports this)
241             15   0         Layer-3 protocol:
242                                      0 = transparent
243                                      1 = transparent with audio features (e.g. DSP)
244                                      2 = Fax G3 Class 2 commands (S14 has to be set to 11)
245                                      3 = Fax G3 Class 1 commands (S14 has to be set to 11)
246             16   250       Send-Packet-size/16
247             17   8         Window-size (not yet implemented)
248             18   4         Bit coded register, Service-Octet-1 to accept,
249                            or to be used on dialout:
250                            Bit 0:    Service 1 (audio) when set.
251                            Bit 1:    Service 5 (BTX) when set.
252                            Bit 2:    Service 7 (data) when set.
253                            Note: It is possible to set more than one
254                                  bit. In this case, on incoming calls
255                                  the selected services are accepted,
256                                  and if the service is "audio", the
257                                  Layer-2-protocol is automatically
258                                  changed to 4 regardless of the setting
259                                  of register 14. On outgoing calls,
260                                  the most significant 1-bit is chosen to
261                                  select the outgoing service octet.
262             19   0         Service-Octet-2
263             20   0         Bit coded register (readonly)
264                            Service-Octet-1 of last call.
265                            Bit mapping is the same as register 18
266             21   0         Bit coded register (readonly)
267                            Set on incoming call (during RING) to
268                            octet 3 of calling party number IE (Numbering plan)
269                            See section 4.5.10 of ITU Q.931
270             22   0         Bit coded register (readonly)
271                            Set on incoming call (during RING) to
272                            octet 3a of calling party number IE (Screening info)
273                            See section 4.5.10 of ITU Q.931
274             23   0         Bit coded register:
275                            Bit 0:    0 = Add CPN to RING message off
276                                      1 = Add CPN to RING message on
277                            Bit 1:    0 = Add CPN to FCON message off
278                                      1 = Add CPN to FCON message on
279                            Bit 2:    0 = Add CDN to RING/FCON message off
280                                      1 = Add CDN to RING/FCON message on
281
282  Last but not least a (at the moment fairly primitive) device to request
283  the line-status (/dev/isdninfo) is made available.
284
285  Automatic assignment of devices to lines:
286
287  All inactive physical lines are listening to all EAZs for incoming
288  calls and are NOT assigned to a specific tty or network interface.
289  When an incoming call is detected, the driver looks first for a network
290  interface and then for an opened tty which:
291
292  1. is configured for the same EAZ.
293  2. has the same protocol settings for the B-channel.
294  3. (only for network interfaces if the security flag is set)
295     contains the caller number in its access list.
296  4. Either the channel is not bound exclusively to another Net-interface, or
297     it is bound AND the other checks apply to exactly this interface.
298     (For usage of the bind-features, refer to the isdnctrl-man-page)
299
300  Only when a matching interface or tty is found is the call accepted
301  and the "connection" between the low-level-layer and the link-level-layer
302  is established and kept until the end of the connection.
303  In all other cases no connection is established. Isdn4linux can be
304  configured to either do NOTHING in this case (which is useful, if
305  other, external devices with the same EAZ/MSN are connected to the bus)
306  or to reject the call actively. (isdnctrl busreject ...)
307
308  For an outgoing call, the inactive physical lines are searched.
309  The call is placed on the first physical line, which supports the
310  requested protocols for the B-channel. If a net-interface, however
311  is pre-bound to a channel, this channel is used directly.
312
313  This makes it possible to configure several network interfaces and ttys
314  for one EAZ, if the network interfaces are set to secure operation.
315  If an incoming call matches one network interface, it gets connected to it.
316  If another incoming call for the same EAZ arrives, which does not match
317  a network interface, the first tty gets a "RING" and so on.
318
3192 System prerequisites:
320
321  ATTENTION!
322
323  Always use the latest module utilities. The current version is
324  named in Documentation/Changes. Some old versions of insmod
325  are not capable of setting the driver-Ids correctly.
326
3273. Lowlevel-driver configuration.
328
329   Configuration depends on how the drivers are built. See the
330   README.<yourDriver> for information on driver-specific setup.
331
3324. Device-inodes
333
334   The major and minor numbers and their names are described in
335   Documentation/devices.txt. The major numbers are:
336
337     43 for the ISDN-tty's.
338     44 for the ISDN-callout-tty's.
339     45 for control/info/debug devices.
340
3415. Application
342
343   a) For some card-types, firmware has to be loaded into the cards, before
344      proceeding with device-independent setup. See README.<yourDriver>
345      for how to do that.
346
347   b) If you only intend to use ttys, you are nearly ready now.
348
349   c) If you want to have really permanent "Modem"-settings on disk, you
350      can start the daemon iprofd. Give it a path to a file at the command-
351      line. It will store the profile-settings in this file every time
352      an AT&W0 is performed on any ISDN-tty. If the file already exists,
353      all profiles are initialized from this file. If you want to unload
354      any of the modules, kill iprofd first.
355
356   d) For networking, continue: Create an interface:
357       isdnctrl addif isdn0
358
359   e) Set the EAZ (or MSN for Euro-ISDN):
360       isdnctrl eaz isdn0 2
361
362     (For 1TR6 a single digit is allowed, for Euro-ISDN the number is your
363      real MSN e.g.: Phone-Number)
364
365   f) Set the number for outgoing calls on the interface:
366       isdnctrl addphone isdn0 out 1234567
367       ... (this can be executed more than once, all assigned numbers are
368            tried in order)
369      and the number(s) for incoming calls:
370       isdnctrl addphone isdn0 in 1234567
371
372   g) Set the timeout for hang-up:
373       isdnctrl huptimeout isdn0 <timeout_in_seconds>
374
375   h) additionally you may activate charge-hang-up (= Hang up before
376      next charge-info, this only works, if your isdn-provider transmits
377      the charge-info during and after the connection):
378       isdnctrl chargehup isdn0 on
379
380   i) Set the dial mode of the interface:
381       isdnctrl dialmode isdn0 auto
382      "off" means that you (or the system) cannot make any connection
383        (neither incoming or outgoing connections are possible). Use
384        this if you want to be sure that no connections will be made.
385      "auto" means that the interface is in auto-dial mode, and will
386        attempt to make a connection whenever a network data packet needs
387        the interface's link. Note that this can cause unexpected dialouts,
388        and lead to a high phone bill! Some daemons or other pc's that use
389        this interface can cause this.
390        Incoming connections are also possible.
391      "manual" is a dial mode created to prevent the unexpected dialouts.
392        In this mode, the interface will never make any connections on its
393        own. You must explicitly initiate a connection with "isdnctrl dial
394        isdn0". However, after an idle time of no traffic as configured for
395	the huptimeout value with isdnctrl, the connection _will_ be ended.
396	If you don't want any automatic hangup, set the huptimeout value to 0.
397        "manual" is the default.
398
399   j) Setup the interface with ifconfig as usual, and set a route to it.
400
401   k) (optional) If you run X11 and have Tcl/Tk-wish version 4.0, you can use
402     the script tools/tcltk/isdnmon. You can add actions for line-status
403     changes. See the comments at the beginning of the script for how to
404     do that. There are other tty-based tools in the tools-subdirectory
405     contributed by Michael Knigge (imon), Volker G��tz (imontty) and
406     Andreas Kool (isdnmon).
407
408   l) For initial testing, you can set the verbose-level to 2 (default: 0).
409      Then all incoming calls are logged, even if they are not addressed
410      to one of the configured net-interfaces:
411      isdnctrl verbose 2
412
413  Now you are ready! A ping to the set address should now result in an
414  automatic dial-out (look at syslog kernel-messages).
415  The phone numbers and EAZs can be assigned at any time with isdnctrl.
416  You can add as many interfaces as you like with addif following the
417  directions above. Of course, there may be some limitations. But we have
418  tested as many as 20 interfaces without any problem. However, if you
419  don't give an interface name to addif, the  kernel will assign a name
420  which starts with "eth". The number of "eth"-interfaces is limited by
421  the kernel.
422
4235. Additional options for isdnctrl:
424
425   "isdnctrl secure <InterfaceName> on"
426   Only incoming calls, for which the caller-id is listed in the access
427   list of the interface are accepted. You can add caller-id's With the
428   command "isdnctrl addphone <InterfaceName> in <caller-id>"
429   Euro-ISDN does not transmit the leading '0' of the caller-id for an
430   incoming call, therefore you should configure it accordingly.
431   If the real number for the dialout e.g. is "09311234567" the number
432   to configure here is "9311234567". The pattern-match function
433   works similar to the shell mechanism.
434
435     ?     one arbitrary digit
436     *     zero or arbitrary many digits
437     [123] one of the digits in the list
438     [1-5] one digit between '1' and '5'
439           a '^' as the first character in a list inverts the list
440
441
442   "isdnctrl secure <InterfaceName> off"
443   Switch off secure operation (default).
444
445   "isdnctrl ihup <InterfaceName> [on|off]"
446   Switch the hang-up-timer for incoming calls on or off.
447
448   "isdnctrl eaz <InterfaceName>"
449   Returns the EAZ of an interface.
450
451   "isdnctrl delphone <InterfaceName> in|out <number>"
452   Deletes a number from one of the access-lists of the interface.
453
454   "isdnctrl delif <InterfaceName>"
455   Removes the interface (and possible slaves) from the kernel.
456   (You have to unregister it with "ifconfig <InterfaceName> down" before).
457
458   "isdnctrl callback <InterfaceName> [on|off]"
459   Switches an interface to callback-mode. In this mode, an incoming call
460   will be rejected and after this the remote-station will be called. If
461   you test this feature by using ping, some routers will re-dial very
462   quickly, so that the callback from isdn4linux may not be recognized.
463   In this case use ping with the option -i <sec> to increase the interval
464   between echo-packets.
465
466   "isdnctrl cbdelay <InterfaceName> [seconds]"
467   Sets the delay (default 5 sec) between an incoming call and start of
468   dialing when callback is enabled.
469
470   "isdnctrl cbhup <InterfaceName> [on|off]"
471   This enables (default) or disables an active hangup (reject) when getting an
472   incoming call for an interface which is configured for callback.
473
474   "isdnctrl encap <InterfaceName> <EncapType>"
475   Selects the type of packet-encapsulation. The encapsulation can be changed
476   only while an interface is down.
477
478   At the moment the following values are supported:
479
480   rawip    (Default) Selects raw-IP-encapsulation. This means, MAC-headers
481            are stripped off.
482   ip       IP with type-field. Same as IP but the type-field of the MAC-header
483            is preserved.
484   x25iface X.25 interface encapsulation (first byte semantics as defined in
485            ../networking/x25-iface.txt). Use this for running the linux
486            X.25 network protocol stack (AF_X25 sockets) on top of isdn.
487   cisco-h  A special-mode for communicating with a Cisco, which is configured
488            to do "hdlc"
489   ethernet No stripping. Packets are sent with full MAC-header.
490            The Ethernet-address of the interface is faked, from its
491            IP-address: fc:fc:i1:i2:i3:i4, where i1-4 are the IP-addr.-values.
492   syncppp  Synchronous PPP
493
494   uihdlc   HDLC with UI-frame-header (for use with DOS ISPA, option -h1)
495
496
497   NOTE:    x25iface encapsulation is currently experimental. Please
498            read README.x25 for further details
499
500
501   Watching packets, using standard-tcpdump will fail for all encapsulations
502   except ethernet because tcpdump does not know how to handle packets
503   without MAC-header. A patch for tcpdump is included in the utility-package
504   mentioned above.
505
506   "isdnctrl l2_prot <InterfaceName> <L2-ProtocolName>"
507   Selects a layer-2-protocol.
508   (With the ICN-driver and the HiSax-driver, "x75i" and "hdlc" is available.
509   With other drivers, "x75ui", "x75bui", "x25dte", "x25dce" may be
510   possible too. See README.x25 for x25 related l2 protocols.)
511
512   isdnctrl l3_prot <InterfaceName> <L3-ProtocolName>
513   The same for layer-3. (At the moment only "trans" is allowed)
514
515   "isdnctrl list <InterfaceName>"
516   Shows all parameters of an interface and the charge-info.
517   Try "all" as the interface name.
518
519   "isdnctrl hangup <InterfaceName>"
520   Forces hangup of an interface.
521
522   "isdnctrl bind <InterfaceName> <DriverId>,<ChannelNumber> [exclusive]"
523   If you are using more than one ISDN card, it is sometimes necessary to
524   dial out using a specific card or even preserve a specific channel for
525   dialout of a specific net-interface. This can be done with the above
526   command. Replace <DriverId> by whatever you assigned while loading the
527   module. The <ChannelNumber> is counted from zero. The upper limit
528   depends on the card used. At the moment no card supports more than
529   2 channels, so the upper limit is one.
530
531   "isdnctrl unbind <InterfaceName>"
532   unbinds a previously bound interface.
533
534   "isdnctrl busreject <DriverId> on|off"
535   If switched on, isdn4linux replies a REJECT to incoming calls, it
536   cannot match to any configured interface.
537   If switched off, nothing happens in this case.
538   You normally should NOT enable this feature, if the ISDN adapter is not
539   the only device connected to the S0-bus. Otherwise it could happen that
540   isdn4linux rejects an incoming call, which belongs to another device on
541   the bus.
542
543   "isdnctrl addslave <InterfaceName> <SlaveName>
544   Creates a slave interface for channel-bundling. Slave interfaces are
545   not seen by the kernel, but their ISDN-part can be configured with
546   isdnctrl as usual. (Phone numbers, EAZ/MSN, timeouts etc.) If more
547   than two channels are to be bundled, feel free to create as many as you
548   want. InterfaceName must be a real interface, NOT a slave. Slave interfaces
549   start dialing, if the master interface resp. the previous slave interface
550   has a load of more than 7000 cps. They hangup if the load goes under 7000
551   cps, according to their "huptimeout"-parameter.
552
553   "isdnctrl sdelay <InterfaceName> secs."
554   This sets the minimum time an Interface has to be fully loaded, until
555   it sends a dial-request to its slave.
556
557   "isdnctrl dial <InterfaceName>"
558   Forces an interface to start dialing even if no packets are to be
559   transferred.
560
561   "isdnctrl mapping <DriverId> MSN0,MSN1,MSN2,...MSN9"
562   This installs a mapping table for EAZ<->MSN-mapping for a single line.
563   Missing MSN's have to be given as "-" or can be omitted, if at the end
564   of the commandline.
565   With this command, it's now possible to have an interface listening to
566   mixed 1TR6- and Euro-Type lines. In this case, the interface has to be
567   configured to a 1TR6-type EAZ (one digit). The mapping is also valid
568   for tty-emulation. Seen from the interface/tty-level the mapping
569   CAN be used, however it's possible to use single tty's/interfaces with
570   real MSN's (more digits) also, in which case the mapping will be ignored.
571   Here is an example:
572
573   You have a 1TR6-type line with base-nr. 1234567 and a Euro-line with
574   MSN's 987654, 987655 and 987656. The DriverId for the Euro-line is "EURO".
575
576   isdnctrl mapping EURO -,987654,987655,987656,-,987655
577   ...
578   isdnctrl eaz isdn0 1      # listen on 12345671(1tr6) and 987654(euro)
579   ...
580   isdnctrl eaz isdn1 4      # listen on 12345674(1tr6) only.
581   ...
582   isdnctrl eaz isdn2 987654 # listen on 987654(euro) only.
583
584   Same scheme is used with AT&E...  at the tty's.
585
5866. If you want to write a new low-level-driver, you are welcome.
587   The interface to the link-level-module is described in the file INTERFACE.
588   If the interface should be expanded for any reason, don't do it
589   on your own, send me a mail containing the proposed changes and
590   some reasoning about them.
591   If other drivers will not be affected, I will include the changes
592   in the next release.
593   For developers only, there is a second mailing-list. Write to me
594   (fritz@isdn4linux.de), if you want to join that list.
595
596Have fun!
597
598 -Fritz
599
600