; First come the span definitions, in the format
;
; span=<span num>,<timing source>,<line build out (LBO)>,<framing>,<coding>,yellow
;
; All T1/E1 spans generate a clock signal on their transmit side. The
; <timing source> parameter determines whether the clock signal from the far
; end of the T1/E1 is used as the master source of clock timing. If it is, our
; own clock will synchronise to it. T1/E1's connected directly or indirectly to
; a PSTN provider (telco) should generally be the first choice to sync to. The
; PSTN will never be a slave to you. You must be a slave to it.
;
; Choose 1 to make the equipment at the far end of the E1/T1 link the preferred
; source of the master clock. Choose 2 to make it the second choice for the master
; clock, if the first choice port fails (the far end dies, a cable breaks, or
; whatever). Choose 3 to make a port the third choice, and so on. If you have, say,
; 2 ports connected to the PSTN, mark those as 1 and 2. The number used for each
; port should be different.
;
; If you choose 0, the port will never be used as a source of timing. This is
; appropriate when you know the far end should always be a slave to you. If the
; port is connected to a channel bank, for example, you should always be its
; master. Any number of ports can be marked as 0.
;
; Incorrect timing sync may cause clicks/noise in the audio, poor quality or failed
; faxes, unreliable modem operation, and is a general all round bad thing.
;

The line build-out (or LBO) is an integer, from the following table

;

0

0 db (CSU) / 0-133 feet (DSX-1)

1

133-266 feet (DSX-1)

2

266-399 feet (DSX-1)

3

399-533 feet (DSX-1)

4

533-655 feet (DSX-1)

5

-7.5db (CSU)

6

-15db (CSU)

7

-22.5db (CSU)

;

framing

:

; one of 'd4' or 'esf' for T1 or 'cas' or 'ccs' for E1 and BRI.
; 'd4' could be referred to as 'sf' or 'superframe'
;

coding

:

; one of 'ami' or 'b8zs' for T1 or 'ami' or 'hdb3' for E1 and BRI.
; * For E1 there is the optional keyword 'crc4' to enable CRC4 checking.
; * If the keyword 'yellow' follows, yellow alarm is transmitted when no
; channels are open.
;
;span=1,0,0,esf,b8zs
;span=2,1,0,esf,b8zs
;span=3,0,0,ccs,hdb3,crc4
;
; Dynamic Spans
;

Next come the dynamic span definitions, in the form

;
; dynamic=<driver>,<address>,<numchans>,<timing>
;
; Where <driver> is the name of the driver (e.g. eth), <address> is the
; driver specific address (like a MAC for eth), <numchans> is the number
; of channels, and <timing> is a timing priority, like for a normal span.
; use "0" to not use this as a timing source, or prioritize them as
; primary, secondard, etc. Note that you MUST have a REAL DAHDI device
; if you are not using external timing.
;

dynamic=eth,eth0/00

02:b3:35:43:9c,24,0

;
; If a non-zero timing value is used, as above, only the last span should
; have the non-zero value.
;
; Channel Configuration
;

Next come the definitions for using the channels. The format is

; <device>=<channel list>
;

Valid devices are

;

e&m

:

; Channel(s) are signalled using E&M signalling (specific
; implementation, such as Immediate, Wink, or Feature Group D
; are handled by the userspace library).

fxsls

:

; Channel(s) are signalled using FXS Loopstart protocol.

fxsgs

:

; Channel(s) are signalled using FXS Groundstart protocol.

fxsks

:

; Channel(s) are signalled using FXS Koolstart protocol.

fxols

:

; Channel(s) are signalled using FXO Loopstart protocol.

fxogs

:

; Channel(s) are signalled using FXO Groundstart protocol.

fxoks

:

; Channel(s) are signalled using FXO Koolstart protocol.

sf

:

; Channel(s) are signalled using in-band single freq tone.

Syntax as follows

;

channel; => sf

<rxfreq>,<rxbw>,<rxflag>,<txfreq>,<txlevel>,<txflag>

;
; rxfreq is rx tone freq in Hz, rxbw is rx notch (and decode)
; bandwith in hz (typically 10.0), rxflag is either 'normal' or
; 'inverted', txfreq is tx tone freq in hz, txlevel is tx tone
; level in dbm, txflag is either 'normal' or 'inverted'. Set
; rxfreq or txfreq to 0.0 if that tone is not desired.
;

unused

:

; No signalling is performed, each channel in the list remains idle

clear

:

; Channel(s) are bundled into a single span. No conversion or
; signalling is performed, and raw data is available on the master.

bchan

:

; Like 'clear' except all channels are treated individually and
; are not bundled. 'inclear' is an alias for this.

rawhdlc

:

; The DAHDI driver performs HDLC encoding and decoding on the
; bundle, and the resulting data is communicated via the master
; device.

dchan

:

; The DAHDI driver performs HDLC encoding and decoding on the
; bundle and also performs incoming and outgoing FCS insertion
; and verification. 'fcshdlc' is an alias for this.

hardhdlc

:

; The hardware driver performs HDLC encoding and decoding on the
; bundle and also performs incoming and outgoing FCS insertion
; and verification. Is subject to limitations and support of underlying
; hardware.

nethdlc

:

; The DAHDI driver bundles the channels together into an
; hdlc network device, which in turn can be configured with
; sethdlc (available separately). In 2.6.x kernels you can also optionally
; pass the name for the network interface after the channel list.

Syntax

;

nethdlc=<channel list>:interface name

; Use original names, don't use the names which have been already registered
; in system e.g eth.
;

dacs

:

; The DAHDI driver cross connects the channels starting at
; the channel number listed at the end, after a colon

dacsrbs

:

; The DAHDI driver cross connects the channels starting at
; the channel number listed at the end, after a colon and
; also performs the DACSing of RBS bits
;
; The channel list is a comma-separated list of channels or ranges, for

example

;
; 1,3,5 (channels one, three, and five)
; 16-23, 29 (channels 16 through 23, as well as channel 29)
;

So, some complete examples are

;
; e&m=1-12
; nethdlc=13-24
; fxsls=25,26,27,28
; fxols=29-32
;
;fxoks=1-24
;bchan=25-47
;dchan=48
;fxols=1-12
;fxols=13-24
;e&m=25-29
;nethdlc=30-33
;clear=44
;clear=45
;clear=46
;clear=47
;fcshdlc=48

dacs=1-24

48

dacsrbs=1-24

48

;
; Tone Zone Data
;
; Finally, you can preload some tone zones, to prevent them from getting
; overwritten by other users (if you allow non-root users to open /dev/dahdi/*
; interfaces anyway. Also this means they won't have to be loaded at runtime.
; The format is "loadzone=<zone>" where the zone is a two letter country code.
;
; You may also specify a default zone with "defaultzone=<zone>" where zone
; is a two letter country code.
;
; An up-to-date list of the zones can be found in the file zonedata.c
;
loadzone = us
;loadzone = us-old
;loadzone=gr
;loadzone=it
;loadzone=fr
;loadzone=de
;loadzone=uk
;loadzone=fi
;loadzone=jp
;loadzone=sp
;loadzone=no
;loadzone=hu
;loadzone=lt
;loadzone=pl
defaultzone=us
;
; PCI Radio Interface
;

(see http

//www.zapatatelephony.org/app_rpt.html)

;
; The PCI Radio Interface card interfaces up to 4 two-way radios (either
; a base/mobile radio or repeater system) to DAHDI channels. The driver
; may work either independent of an application, or with it, through
; the driver;s ioctl() interface. This file gives you access to specify
; load-time parameters for Radio channels, so that the driver may run
; by itself, and just act like a generic DAHDI radio interface.
;
; Unlike the rest of this file, you specify a block of parameters, and
; then the channel(s) to which they apply. CTCSS is specified as a frequency
; in tenths of hertz, for example 131.8 HZ is specified as 1318. DCS
; for receive is specified as the code directly, for example 223. DCS for
; transmit is specified as D and then the code, for example D223.
;
; The hardware supports a "community" CTCSS decoder system that has
; arbitrary transmit CTCSS or DCS codes associated with them, unlike
; traditional "community" systems that encode the same tone they decode.
;
; this example is a single tone DCS transmit and receive
;

specify the transmit tone (in DCS mode this stays constant)

;tx=D371
;

specify the receive DCS code

;dcsrx=223
;
; this example is a "community" CTCSS (if you only want a single tone, then
; only specify 1 in the ctcss list)
;

specify the default transmit tone (when not receiving)

;tx=1000
;
; Specify the receive freq, the tag (use 0 if none), and the transmit code.
; The tag may be used by applications to determine classification of tones.
; The tones are to be specified in order of presedence, most important first.
; Currently, 15 tones may be specified..
;
;ctcss=1318,1,1318
;ctcss=1862,1,1862
;
; The following parameters may be omitted if their default value is acceptible
;

Set the receive debounce time in milliseconds

;debouncetime=123
;

set the transmit quiet dropoff burst time in milliseconds

;bursttime=234
;
; set the COR level threshold (specified in tenths of millivolts)
; valid values are {3125,6250,9375,12500,15625,18750,21875,25000}
;corthresh=12500
;
; Invert COR signal {y,n}
;invertcor=y
; Set the external tone mode; yes, no, internal {y,n,i}
;exttone=y
;

Now apply the configuration to the specified channels

;
; We are all done with our channel parameters, so now we specify what
; channels they apply to
;channels=1-4
;
; Overiding PCM encoding
;

; Usually the channel driver sets the encoding of the PCM for the

channel (mulaw / alaw. That is

g711u or g711a). However there are

; some cases where you would like to override that. 'mulaw' and 'alaw'
; set different such encoding. Use them for channels you have already
; defined with e.g. 'bchan' or 'fxoks'.
;mulaw=1-4
;alaw=1-4
;
; 'deflaw' is similar, but resets the encoding to the channel driver's
; default. It must be useful for something, I guess.
;mulaw=1-10
;deflaw=5
;
; Echo Cancellers
;