Xorcom Astribank Documentation
==============================
Xorcom Team <support@xorcom.com>
$Revision: 8948 $, $Date: 2010-07-20 06:23:39 -0500 (Tue, 20 Jul 2010) $

This file documents the DAHDI drivers for the Xorcom Channel Bank.

It is generally a more technical document than the 
http://www.xorcom.com/product-manuals/product-manuals.html[Astribank 
User Manual]

An HTML version of the latest version of this document could be found at 
http://docs.tzafrir.org.il/dahdi-tools/README.Astribank.html[]

Introduction
------------
The Xorcom Astribank is a USB-connected channel-bank. An Astribank may
have up to 4 modules:

PRI:: 
  1, 2 or 4 ports of E1 or T1. Can only be the first (left-most) module
  of the Astribank. Note that each port has physically a pair of ports,
  where the top one has crossed wiring.

BRI::
  2, 4 or 8 ports of BRI. Can only be used as the first (left-most)
  module of the Astribank. 

FXO::
  8 ports of FXO (connector to an analog PSTN line).

FXS::
  8 ports of FXS (connector to an analog phone). If used as the first
  (left-most) module, it will also have 2 output lines and 4 input lines
  that will appear on DAHDI like standard DAHDI ports. The input and
  output ports are connected from the two RJ-45 connectors on the right
  side of the module.

There is also a 6FXS-2FXO module that is essentially an FXS module with
six lines instead of 8 (but still with the input and output ports) and
an FXO module of two ports.


Building and Installation
-------------------------
Apart from the standard DAHDI build requirements, you also need libusb
development headers to build the fpga_load firmware loader. This is
typically the package libusb-dev on Debian (and derivatives like Ubuntu)
or libusb-devel on RedHat (and derivatives like CentOS/Trixbox).

Patch for BRI
~~~~~~~~~~~~~
(As of DAHDI 2.2 this patch is no longer needed. Furthermore, it does
not apply. The same directory has a newer patch that applies. This
section is kept in the document for the time being for the benefit of
those with older versions)

In order for the BRI module (xpd_bri.ko) to build, you still need an
external patch: 

http://updates.xorcom.com/astribank/bristuff/dahdi_bri_dchan.diff[]

You need to apply it to the dahdi-linux tarball before building:

  wget http://updates.xorcom.com/astribank/bristuff/dahdi_bri_dchan.diff
  patch -p1 <dahdi_bri_dchan.diff


Installation Scenarios
~~~~~~~~~~~~~~~~~~~~~~
Below are some commented sequences of commands that can be used at some
common scenarios. Those scenarios begin only after you installed the
software (dahdi-linux, dahdi-tools, asterisk, etc.).

New Installation Scenario
^^^^^^^^^^^^^^^^^^^^^^^^^
Installing Astribank on a system where there's no existing Astribank.
You install the driver when the Astribank was already connected:

--------------------------------------------
# If you had the hardware already connected: Load just the USB firmware
/usr/share/dahdi/xpp_fxloader usb
# (you could use 'load' instead of 'usb' but this is also a good test
# that automatic load through firmware is also in place)
dahdi_hardware -v
# wait until the Astribank has a product ID of 11x2
sleep 5 # Just wait a little bit 
dahdi_hardware -v # now that you see that all's well:
/etc/init.d/dahdi start
# generate configuration:
dahdi_genconf
# Apply it:
dahdi_cfg

# edit /etc/asterisk/chan_dahdi.conf to #include dahdi-channels.conf or
# copy its content to the end of chan_dahdi.conf
#
# This stops existing DAHDI calls, if any, but does no other harm:
asterisk -rx 'dahdi restart' 
--------------------------------------------


Upgrade Scenario
^^^^^^^^^^^^^^^^
Upgrading is roughly the same as a new installation. But in many cases 
you begin with  resetting the firmware.

I also assume here that the configuration is valid, and hence I don't
generate it.

--------------------------------------------
# If you need to reset the firmware:
/usr/share/dahdi/xpp_fxloader reset
# (you could use 'load' instead of 'usb' but this is also a good test
# that automatic load through firmware is also in place)
dahdi_hardware -v
# wait until the Astribank has a product ID of 11x2
sleep 5 # Just wait a little bit
dahdi_hardware -v # now that you see that all's well:
/etc/init.d/dahdi start
#
# This stops existing DAHDI calls, if any, but does no other harm:
asterisk -rx 'dahdi restart' 
--------------------------------------------


Sample Configurations
---------------------
We generally recommend to generate the configuration by using utility
dahdi_genconf which are included with DAHDI. Nevertheless, the following 
can serve as reference configurations for a system where Astribank devices 
are used.

Also refer to the general README for documentation of the other DAHDI
configuration files.

xpp.conf: Astribank Initialization
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/etc/dahdi/xpp.conf is read by the initialization scripts of Astribank
modules:
-----------------------------------------------------------
# /etc/dahdi/xpp.conf
#
# This file is used to configure the operation
# of init_card_* initialization scripts.
#

# Adds many more tracing messages that are sent to syslog:
#debug		1

# xpd_pri: E1 or T1. The default is E1 for all the ports.
#   Setting T1 instead:
#pri_protocol	T1
#
#  Or if you actually want to mix E1 and T1:
#pri_protocol/xbus-00/xpd-02	T1
#pri_protocol/connector:usb-0000:00:1d.7-7/xpd-03	T1
#pri_protocol/label:usb:0000183/xpd-03	T1
# If several definitions can refer to a port, the last wins. 
# If none applies, the default of E1 holds.

#  FXO: country to adjust settings to:
#opermode	FRANCE

#  Don't run power calibration on the FXS units. This can save time
#  but can also get you unit randomly disconnect, if badly used:
#fxs_skip_calib	1
-----------------------------------------------------------


xpp_order: Explicitly order Astribanks
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
(This feature is available as of DAHDI 2.2)

On a system with multiple Astribank you would normally want to guarantee
that Astribanks are registered in the same order regardless of the order
in which they are connected or detected. Assuming that you register them
all at the same time. In order to do that, you should list the
Astribanks explicitly under /etc/dahdi/xpp_order .

Astribanks that are listed there are registered first (according to the
order of lines in the files). Astribanks not listed there are added
last, and sorted by the 'USB connector' string.

You can identify an Astribank in two ways: 

Label::
  each Astribank (except some really old ones) has a label . This 
  identifies the actual Astribank box.

Connector::
  Identify the path the Astribank is connected through. E.g.: to what
  USB port you connected it.

Identifying an Astribank by the label seems simpler and more
predictable. Though it may have some slightly surprising effects if
replace one Astribank with another.

The sample configuration file:
-----------------------------------------------------------
#
# This is an optional configuration file for ordering
# Dahdi registration.
#
# It is read from /etc/dahdi/xpp_order. This location
# may be overriden via the environment variable XPPORDER_CONF
#
# Lines may contain:
#   - The Astribank label (verbatim)
#   - The Astribank connector string (prefixed with @)
# Ordering number of each listed Astribank is determined
# by its position in this file.
# Astribanks not listed in this file, get an ordering
# number of 99 (last).
#
# Astribanks with same ordering number are sorted by their
# connectors (to preserve legacy behaviour).
#
# Examples:
#usb:1234
#@usb-0000:06:02.2-2
-----------------------------------------------------------

In order to generate one that includes all the Astribanks in the system
with the current order in which they are connected, use:

  dahdi_genconf xpporder

For more technical details see the section <<_registering_in_dahdi>>
below.


/etc/dahdi/system.conf
~~~~~~~~~~~~~~~~~~~~~~

Astribank 8
^^^^^^^^^^^
    fxoks=1-14

Astribank 6FXS/2FXO
^^^^^^^^^^^^^^^^^^^
    fxoks=1-12
    fxsks=13-14

Astribank 16: 8FXS/8FXO
^^^^^^^^^^^^^^^^^^^^^^^
    fxoks=1-14
    fxsks=15-22

Astribank 4 BRI
^^^^^^^^^^^^^^^
    # Assumed ports settings:
    # Ports 1,3: TE
    # Ports 2,4: NT
    span=1,1,1,ccs,ami
    span=2,0,1,ccs,ami
    span=3,2,1,ccs,ami
    span=4,0,1,ccs,ami
    bchan=1-2,4-5,7-8,10-11
    ; if you applied the bri_dchan patch:
    ;dchan=3,6,9,12
    hardhdlc=3,6,9,12

Astribank 4 PRI E1
^^^^^^^^^^^^^^^^^^
    # Assumed ports settings:
    # Ports 1,3: TE (CPE)
    # Ports 2,4: NT (Net)
    span=1,1,1,ccs,hdb3,crc4
    span=2,0,1,ccs,hdb3,crc4
    span=3,2,1,ccs,hdb3,crc4
    span=4,0,1,ccs,hdb3,crc4
    bchan=1-15,17-30,31-45,47-60,61-75,77-90,91-105,107-120
    dchan=16,46,76,106

Astribank 4 PRI T1
^^^^^^^^^^^^^^^^^^
    # Assumed ports settings:
    # Ports 1,3: TE (CPE)
    # Ports 2,4: NT (Net)
    span=1,1,1,esf,b8zs
    span=2,0,1,esf,b8zs
    span=3,2,1,esf,b8zs
    span=4,0,1,esf,b8zs
    bchan=1-23,25-47,49-71,73-95
    dchan=24,48,72,96
  

/etc/asterisk/chan_dahdi.conf
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Astribank 8
^^^^^^^^^^^   
    [channels]
    signalling=fxo_ks
    ; The real analog ports:
    context=from-internal
    echocancel=yes
    ; echocancelwhenbriged=yes
    ; echotraining=no
    channel => 1-8

    ; output ports:
    context=astbank-output
    channel => 9-10
    ; input ports:
    immediate=yes
    context=astbank-input
    channel => 11-14
    immediate=no

Astribank 6FXS/2FXO
^^^^^^^^^^^^^^^^^^^   
    [channels]
    signalling=fxo_ks
    ; The real analog ports:
    context=from-internal
    echocancel=yes
    ; echocancelwhenbriged=yes
    ; echotraining=no
    channel => 1-6

    ; output ports:
    context=astbank-output
    channel => 7-8
    ; input ports:
    immediate=yes
    context=astbank-input
    channel => 9-12
    immediate=no

    ; FXO ports
    signalling=fxs_ks
    context=from-pstn
    callerid=asreceived
    channel => 13-14

Astribank 16: 8FXS/8FXO
^^^^^^^^^^^^^^^^^^^^^^^   
    [channels]
    signalling=fxo_ks
    ; The real analog ports:
    context=from-internal
    echocancel=yes
    ; echocancelwhenbriged=yes
    ; echotraining=no
    channel => 1-8

    ; output ports:
    context=astbank-output
    channel => 9-10
    ; input ports:
    immediate=yes
    context=astbank-input
    channel => 11-14
    immediate=no

    ; FXO ports
    signalling=fxs_ks
    context=from-pstn
    callerid=asreceived
    channel => 15-22

Astribank 4 BRI
^^^^^^^^^^^^^^^    
    ; Assumed ports settings:
    ; Ports 1,3: TE
    ; Ports 2,4: NT
    [channels]
    switchtype = euroisdn
    callerid = asreceived
    
    ; TE ports:
    signalling = bri_cpe_ptmp
    ;signalling = bri_cpe
    context = from-pstn
    group = 1,11
    channel => 1,2
    
    group = 1,13
    channel => 7,8
    
    ; NT ports:
    signalling = bri_net_ptmp
    ;signalling = bri_net
    context = from-internal
    group = 2,12
    channel => 4,5
    
    group = 2,14
    channel => 10,11

Astribank 4 PRI E1
^^^^^^^^^^^^^^^^^^ 
    ; Assumed ports settings:
    ; Ports 1,3: TE
    ; Ports 2,4: NT
    [channels]
    switchtype = euroisdn
    callerid = asreceived
    
    ; TE ports:
    signalling = pri_cpe
    context = from-pstn
    group = 1,11
    channel => 1-15,17-30
    
    group = 1,13
    channel => 61-75,77-90
    
    ; NT ports:
    signalling = pri_net
    ;signalling = pri_net
    context = from-internal
    group = 2,12
    channel => 31-45,47-60
    
    group = 2,14
    channel => 91-105,107-120

Astribank 4 PRI T1
^^^^^^^^^^^^^^^^^^ 
    ; Assumed ports settings:
    ; Ports 1,3: TE
    ; Ports 2,4: NT
    [channels]
    switchtype = national
    callerid = asreceived
    
    ; TE ports:
    signalling = pri_cpe
    context = from-pstn
    group = 1,11
    channel => 1-23
    
    group = 1,13
    channel => 49-71
    
    ; NT ports:
    signalling = pri_cpe
    ;signalling = pri_net
    context = from-internal
    group = 2,12
    channel => 25-47
    
    group = 2,14
    channel => 73-95


/etc/asterisk/extensions.conf
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sample dialplan (extensions.conf) for all the above:

-----------------------------------------------------------
[phones-dahdi]
; With Asterisk 1.4 you will may need to use here 'Zap' instead of
; DAHDI. See Zaptel-to-DAHDI.txt .
;
; 6001 will dial to channel 1, 6020, to DAHDI channel 20, etc.
exten => _6XXX,1,Dial(DAHDI/${EXTEN:1})
; Useful for debugging trunks. Will potentially allow users to
; bypass context limitations.
;exten => _6XXX.,1,Dial(DAHDI/${EXTEN:1:3}/${EXTEN:4})

[trunk]
; A number that begins with 9: dial it through a trunk
; (we put FXO channels and TE channels in group 0).
; The leading 9 is stripped.
exten => _9.,1,Dial(DAHDI/g0/${EXTEN:1})
; dialing a number that begins with 83 will dial it through
; span 3, and so forth. The two leading digits are stripped.
; (Each digital span is also added to group 10+span number).
exten => _8X.,1,Dial(DAHDI/g1${EXTEN:1:1}/${EXTEN:2})

[from-internal] 
; The context of FXS ports: analog phones.
; They are allowed to dial to all other phones 
include => phones-dahdi 
; They are also allowed to call through the trunk: 
include => trunk
; some simple tests:
include => astbank-test

[from-pstn] 
; Calls from the PSTN enter here. Redirect calls to an IVR 
; or a default extension in the s context here. In this case we  
; redirect calls to DAHDI channel 1: 
exten => s,1,Dial(DAHDI/1) 

; Alternatively, the following will redirect you to the demo IVR 
; from the sample extensions.conf of Asterisk:
include => demo

; An extra context with some simple tests
[astbank-test]
; 200: echo test
exten => 200,1,Answer
exten => 200,n,Wait(1)
exten => 200,n,Echo()
exten => 200,n,Hangup

; 203: say extension number. Will only work if caller ID 
; is properly set in chan_dahdi.conf / dahdi-channels.conf
exten => 203,1,Answer
exten => 203,n,Wait(1)
exten => 203,n,SayNumber(${CALLERID(num)})
exten => 203,n,Hangup

[astbank-input] 
exten => s,1,Set(DAHDI_CHAN=${CUT(CHANNEL,-,1)}) 
exten => s,n,Set(DAHDI_CHAN=${CUT(DAHDI_CHAN,/,2)}) 
; 11 is the number of the first input port. At least in the sample 
; configuration below. 
;exten => s,n,Set(INPUT_NUM=$[${DAHDI_CHAN}-11)]) 
; The sample below just logs the signal.  
exten => s,n,NoOp(Got signal from DAHDI Channel ${DAHDI_CHAN}) 
; Alternatively: 
;exten => s,n,System(run something) 

; No. We did not forget the context astbank-outputs. Output 
; ports only get calls from the PBX. Thus they don't need a context 
; of their own. Sending them to a context of their on makes 
; 'dahdi show channels' in the CLI provide useful display, though.
-----------------------------------------------------------


Troubleshooting
---------------
The following commands provide useful information for debugging:

lsusb Test
~~~~~~~~~~
Check USB level status. You can use one of the following utilities for it:

  dahdi_hardware -v
       or
  lsusb | grep e4e4

- Look for the USB Product ID (the second number after e4e4).
- If you see *11x2* (e.g: 1152)- the FPGA firmware has been loaded.
  Move on.
  dahdi_hardware will also show you some more details if the driver
  is loaded while the lsusb will just list the device.
- If it shows something as product ID *11x0* - the USB firmware is not
  loaded. Maybe you need to run fxload. Or maybe just unplug and plug again
  the device. Also make sure that you have fxload installed.
- If lsusb shows the Product ID as *11x1* - only the USB firmware is loaded 
  and not the FPGA firmware is loaded. If this is still the case after 
  a while - either the firmware loading has failed or you don't have
  fpga_load. Make sure you have libusb-dev(el) installed when
  building DAHDI. After you have installed it, you may need to re-run
  ./configure .
- It should list all of your Astribank devices. If it doesn't (for
  more than period of time needed for the initial firmware
  loading) - Check that the Astribank is connected indeed.


DAHDI Registration
~~~~~~~~~~~~~~~~~~
Check if the Astribank spans are registered with DAHDI:

  dahdi_registration

- This should give useful results after the drivers have identified
  and your devices are initialized.
- It should list all Astribank XPDs. For each of them it should write
  "on" or "off". If the registration status is "off", then it means that
  the span has not been registered in DAHDI and therefore can not be used
  yet.
- Registration is normally done as part of `/etc/init.d/dahdi start`.
  If you want to register the spans manually, then run command:
  `dahdi_registration on` .


DAHDI Level Information
~~~~~~~~~~~~~~~~~~~~~~~
You can get some information regarding DAHDI channels by running one of the
following commands:

    lsdahdi
       or
    cat /proc/dahdi/*

- Those two are almost the same. The lsdahdi produced more correctly sorted
  output if you have more than 10 spans, and also make the output listing
  looks a little bit nicer.
- You can see if your DAHDI spans and channels were loaded, if
  they were configured by dahdi_cfg and if they are in use (typically by
  Asterisk).
  For example:
  Not configured Astribank FXS channel will be displayed as:

     42 FXS

- When *dahdi_cfg* has applied the configuration of the channel (from 
  /etc/dahdi/system.conf), you will see an extra column for the signalling
  type of the channel. The same channel after it has been configured:

    42 FXS        FXOKS

- If a program (which is typically Asterisk) uses it, you'll see:

    42 FXS        FXOKS      (In use)



Asterisk Level Information
~~~~~~~~~~~~~~~~~~~~~~~~~~
  asterisk -rx 'dahdi show channels'

- If you get error "Unable to connect to remote asterisk" then it
  means that the Asterisk is not running. It is possible that Asterisk
  has failed to start due to misconfigured chan_dahdi.conf or whatever reason.
  Check /var/log/asterisk/messages or /var/log/asterisk/full .
- If you get the error that "there is no such command" then it means that
  chan_dahdi.so is not loaded. There are two reasons for such problem:
  * chan_dahdi.so is not even built. Check if the file exists:

       ls -l /usr/lib/asterisk/modules/chan_dahdi.so

  * the chan_dahdi.so file exists but it is not loaded. Try to load it manually:

       asterisk -rx 'load module chan_dahdi.so'

- You see "pseudo" channel only. It means that you have not configured any
  channels. If you have configured channels in chan_dahdi.conf, you may
  need either to restart the Asterisk or unload/load chan_dahdi.so manually.
  You can use the following Asterisk CLI commands for it: `unload chan_dahdi.so` 
  and `load chan_dahdi.so`


Known Issues
~~~~~~~~~~~~
Empty /proc dir
^^^^^^^^^^^^^^^
.Symptoms:
- Error message:

  "ERR-xpd_fxo: XBUS-00/XPD-00: Failed initializing registers (-22)"
  
- Likewise for all XPDs. 
- The directory /proc/xpp exists but is empty (not even the files 
  'xbuses' and 'sync').

.Cause:
The driver failed to recreate the procfs directory /proc/xpp and hence
everything under it. This is because it has already existed. And it
existed because a process still uses it. This is typically because you
have a shell whose working directory is /proc/xpp or somewhere under
it:

  # lsof /proc/xpp
  COMMAND  PID USER   FD   TYPE DEVICE SIZE       NODE NAME
  bash    2741 root  cwd    DIR    0,3    0 4026532684 /proc/xpp

.Fix:
Move that process from that directory, or close the file it uses from
under /proc/xpp and reload the dahdi / xpp drivers.


Bad Firmware Version
^^^^^^^^^^^^^^^^^^^^
.Symptoms:
- An Astribank finishes initialization quickly, the /proc/XBUS-nn
  directory has no XPD-mm subdirectories.
- Error in the kernel logs about:

  NOTICE-xpp: XBUS-00: XPD at 00: type=6.0 has bad firmware revision 2.6 

.Cause:
This is normally caused by an Astribank with an older firmware connected
to a 

The protocol version supported by the firmware will typically be the same 
one as in the device initialization scripts installed to 
/usr/share/dahdi . Hence if this version installed 
`/usr/share/dahdi/init_card_3_29` it will probably include firmware of 
protocol version 29.

.Fix:
Reset the firmware:

  /usr/share/dahdi/xpp_fxloader reset

Or disconnect the Astribank from the power and reocnnect. On some older 
versions of the USB firmware resetting the firmware (or any operation of 
fpga_load) would fail if the driver is loaded. Hence you would need to 
run `rmmod xpp_usb` . In the end, reload the drivers.


USB Errors at Shutdown
^^^^^^^^^^^^^^^^^^^^^^
.Symptoms:
You see USB-related errors similar to the following whenever you shut
down the drivers of the Astribank or disconnect its drivers:

  ERR-xpp_usb: XBUS-00: Failed to submit a receive urb

.Cause:
This is a normal part of the shutdown of the USB connection. 

.Fix:
Ignore them. Unless the USB should not have disconnected at that time.


BRI Layer 1 Down
^^^^^^^^^^^^^^^^
.Symptoms:
With the BRI module only, and not in the middle of an active call, you
notice that suddenly the line goes down. The LED of the port stops
blinking, layer1 not listed as "active" in the bri_info file in
/proc/xpp, and the span is in RED alarm in DAHDI.

You may also see an error message such as:

  NOTICE-xpd_bri: XBUS-00/XPD-02: D-Chan RX Bad checksum: [2A:01=FC] (252)

from the exact time of the disconnecting.

.Cause:
This is expected with most european BRI PtMP providers. If they support
PtMP, they are normally also expected to support ISDN phones, that get
the power from the provider. And thus they shut down the line whenever
there's no active call. 

Sometimes the line is shut down in the middle of a layer 2 message. In
the BRI driver the HDLC decoding/encoding is done in the card. In that
case we may get the above error.

.Fix:
Normaly this is not a problem. The driver will re-establish a connection
once a new call needs to be made.


Astribank in lsusb but not in dahdi_hardware
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.Symptoms:
You fail to find an Astribank device in the output of lsusb . But you
see it in `lsusb | grep e4e4`

.Cause:
The perl module Dahdi::Hardware currently relies on
/proc/bus/usb/devices (from usbfs) whereas lsusb can use either that or
/dev/bus/usb . 

.Fix:
Usbfs is generally deprecated and some distributions (OpenSUSE, Ubuntu) no 
longer mount it by default. Try:

  mount /proc/bus/usb

and if that doesn't work:

  mount -t usbfs usbfs /proc/bus/usbfs

However this is generally a cosmetic issue that only affects the listing
in dahdi_hardware.


Astribank not initialized: Premature packet end
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.Symptoms:
After upgrading to Zaptel 1.4.12 / 1.2.25 the initialization of the
Astribank times out. In the logs you see:

  kernel: NOTICE-xpp: XBUS-00(00): FIRMWARE: ERROR_CODE CODE = 0x3 (Premature packet end) 

.Cause:
When an Astribank is detected, the driver asks it what is its version
and what components it has. Normally if the version of the firmware and
of the driver does not match the driver gives an ugly message and fails
the initialization.

However in the change of the protocol between versions 2.9 (29) and 3.0
(30), the response that the new driver receives from a device with the
old version is now considered to be an illegal packet and gets
discarded. As a result, the Astribank waits till time-out for the
initialization to end.

.Fix:
Reset the firmware of the Astribank by either:

  /usr/share/dahdi/xpp_fxloader reset

or disconnecting it from the power and reconnecting it.


Reference
---------
LEDs Indication
~~~~~~~~~~~~~~~
The Astribank has 4 global indication leds and one or two per-port leds.
On some of the models the LEDs are located on the left side on the front
panel. If there are no separate LEDs there, then the red LEDs of the
upper left-most ports of the device are used as the indication LEDs. Don't 
confuse them with green port status LEDs.

The first led is the "Power" led. It is on if the unit gets power.
The second led is the "Active" led, which is on when there is at 
least one "active" port (in a call / off-hook, though the meaning of this is 
different in BRI).
The last led is called "Hardware OK", but is actually only is on in case of  
the hardware failure.

The third led is the "Sync" led. If it blinks, the device is synchronized 
with the driver on the computer. If the device is selected to be the  
synchronization source for all of the Astribank devices then it will blink
a quick single blink.
If the device gets synchronization from the driver, it will blink in a 
more steady frequency.

"Double blink" indicates that the unit has an FXO module, and still is
getting synchronization from the computer, and is not the synchronization
source.

The per-port green led on analog (both FXS and FXO) indicates that the
port is off-hook.

On the BRI, the green led indicates a TE port whereas an orange led
indicates an NT port. If the led is solid, the port is down (not even
layer-1 connection is up). If it is blinking a double blink, layer 1
is up. A slower single blinking indicates that layer 2 is up as well
(which means that Asterisk is driving the port).

As for the leds of the PRI ports, see the next section.


PRI Ports Configuration
~~~~~~~~~~~~~~~~~~~~~~~
Astribank PRI module has two RJ-45 sockets for each PRI port. The lower
socket provides typical PRI CPE side wiring: Rx- pins 1,2; Tx - pins 
4,5. The upper socket provides typical PRI Network side  wiring: Rx- pins
4,5; Tx - pins 1,2. The both sockets are permanently active and you can 
use any of them regardless of any configuration parameters (Both
connectors are live. And connecting both of them with a flat 8-wire
ethernet cable is a simple way to do a loop test for the port).

Each port in the PRI module can be configured either as E1 or T1. 
The default is E1, but it can be changed in xpp.conf (See the section
above).

In addition to that, a port defaults to consider itself a CPE, or
rather, to accept timing from the remote party. To override that you
need to set the timing value to 0 (second parameter in the 'span=' line
in system.conf).

Thus the following in system.conf will also set an orange LED:

  span=2,0,3,ccs,hdb3,crc4

Note that as this is only applied when dahdi_cfg is run, the port will have
the default green LED lit at the bottom until it is configured.


Voicemail Indication
~~~~~~~~~~~~~~~~~~~~
Asterisk supports several forms of voicemail message waiting indication
(VMWI) on a phone connected to a FXS port. One of them is a stutter tone
sent when the phone is picked up. Another one is an FSK tone that
encodes the number of messages waiting (or 0, for none). Alternatively it
may send an ioctl call on the channel (DAHDI_VMWI) to indicate the VMWI
status on the channel.

The DAHDI FXS device may implement any of extra three VMWI notification
methods. The Astribank currently only supports one of them (AC neon LED).
With Asterisk, as of 1.6.2 you can enable that using the following line
in the channel's config in chan_dahdi.conf:

 mwisendtype = neon 

Versions of Asterisk before 1.6.0 did not support this ioctl. You will
need to reset the module parameter <<_vmwi_ioctl,vmwi_ioctl>>.


Device Startup
~~~~~~~~~~~~~~
This section describes in great depth the initialization of the Xorcom
Astribank. Normally it would not be really needed, as the standard
installation of DAHDI should put everything in place. This is generally
some documentation to read when things fail.

Terminology
^^^^^^^^^^^
There are some technical terms that are used in this document and in the
driver / dahdi.

span::
  DAHDI breaks the channels it knows about to logical units called
  "spans". A port in a E1/T1/ISDN card is usually a span. An whole
  analog card is also a "span". You can see the list of spans as the list
  of files under /proc/dahdi directory or in output of the dahdi_tool
  utility.

XBUS::
  A funny way to call an Astribank device.

XPD::
  Basically this is a logical unit of the Astribank. It will be 
  registered in DAHDI as a single span. This can be either an analog 
  (FXS or FXO) module or a single port in case of a BRI module.


Loading Firmware
^^^^^^^^^^^^^^^^
Normally this is done using the script /usr/share/dahdi/xpp_fxloader.
If it works fine, you don't need to bother reading this section.
Once the firmware is loaded the USB Vendor ID and Product ID of the Astribank
became to be e4e4 11x2, and now the driver can pick it up.

First and foremost: the simplest and most useful tool to debug problems
is lsusb. The output of lsusb should show you if the device is connected
if its firmware is loaded. 

The firmware files are named *.hex. They are presented in the Intel hex
format. The files are copied from xpp/utils to /usr/share/dahdi folder 
during the DAHDI installation.

The Astribank needs a firmware loaded into it. Without the firmware, 
the device will appear in lsusb with Vendor ID e4e4 and Product ID 11x0
(1130, 1140, 1150, 1160 or 1163. 1163 behaves almost exactly as 1160).
The firmware loading process consists of two
stages. In the first stage the "USB" firmware is loaded by using program
fxload. When the first stage is completed the Vendor ID is e4e4 and the
Product ID is 11x1. (e.g. 1151 if it were 1150 previously).

You can use the following command in order to load the "USB" firmware
manually:

  fxload -t fx2 -D /dev/bus/usb/MMM/NNN -I /usr/share/dahdi/USB_FW.hex

where,

fxload::
  A standard program that is typically part either of package 'fxload' 
  or 'hotplug-utils' . 
/dev/bus/usb::
  On some old systems it is missing . /proc/bus/usb (usbfs) could be
  used instead.
MMM::
  the first number (bus number)
NNN::
  the second number (device number) you see for the device in lsusb

If the loading process has been completed successfully, the device 
disconnects and then connects again itself with USB Product ID 11x1 
(and a new device number).

In the second stage, the "FPGA" firmware is loaded.
The second-stage firmware loading is performed by using program fpga_load, 
which is built in the directory xpp/utils and then copied to folder 
/usr/sbin during DAHDI installation.

The command syntax is similar to the syntax of fxload. You can use the 
following command in order to load the FPGA firmware manually:

  # pick the right name according to the device ID. FPGA_1161.hex is for
  # 116x Astribanks:
  astribank_hexload -D /dev/bus/usb/MMM/NNN -F /usr/share/dahdi/FPGA_1161.hex
  # Note the shell expantion in this line:
  astribank_hexload -D /dev/bus/usb/MMM/NNN -p /usr/share/dahdi/PIC_TYPE_[1-4].hex
  # reenumerate (disconnect and reconnect)
  astribank_tool  -D /dev/bus/usb/MMM/NNN -n

With older USB firmwares (before the one included in e.g. dahdi-linux
2.2) you needed to use instead of all the above:

  # pick the right name according to the device ID. FPGA_1151.hex is for
  # 115x Astribanks:
  fpga_load -D /dev/bus/usb/MMM/NNN -I /usr/share/dahdi/FPGA_1151.hex

Please note, that  NNN value differs from that that was used for the 
fxload command due to the fact that device has "reconnected" itself 
with another Product ID number. So you need to run lsusb again and get 
the new NNN value. Usually, the new value is equal to the old value 
incremented by 1.

On newer systems (e.g. Centos 4) /dev/bus/usb may not be available. In
that case, use /proc/bus/usb . usbfs should be mounted there.


Automatic Firmware Loading
^^^^^^^^^^^^^^^^^^^^^^^^^^
Udev is a framework for dynamic device nodes, which is supported in
kernel 2.6. if your udev rules are properly  configured then the 
firmware should be loaded automatically and you will see product ID 11x2
(e.g.: 1152). 

Udev is mostly configured by files under /etc/udev/rules.d . The
installer of dahdi-linux installs drivers/dahdi/xpp/xpp.rules into that
directory.

This file instructs udev to run /usr/share/dahdi/xpp_fxloader for each
time an Astribank connects and needs firmware. When the Astribank loads
firmware or when it resets its firmware it "reenumerates" - disconnects
and reconnects as a new device. 

Below are kernel log messages of an Astribank loading firmware. It firs
connects without any firmware (device no. 44). Udev tells it to load the
USB firmware. It disconnects and reconnects (45). This Udev gets the
FPGA firmware loaded into it. It disconnects again, and when it
reconnects it is now ready to talk with the driver. The last message is
from the driver.
-------------------------------------
usb 7-1: configuration #1 chosen from 1 choice
usb 7-1: New USB device found, idVendor=e4e4, idProduct=1150
usb 7-1: New USB device strings: Mfr=0, Product=0, SerialNumber =0
usb 7-1: USB disconnect, address 44
usb 7-1: new high speed USB device using ehci_hcd and address 45
usb 7-1: configuration #1 chosen from 1 choice
usb 7-1: New USB device found, idVendor=e4e4, idProduct=1151
usb 7-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 7-1: Product: Astribank
usb 7-1: Manufacturer: Xorcom LTD
usb 7-1: SerialNumber: 00000123
usb 7-1: USB disconnect, address 45
usb 7-1: new high speed USB device using ehci_hcd and address 46
usb 7-1: configuration #1 chosen from 1 choice
usb 7-1: reset high speed USB device using ehci_hcd and address 46
INFO-xpp_usb: XUSB: Xorcom LTD -- Astribank -- FPGA
-------------------------------------

Another useful tool for tracing UDEV-related issue is the udev monitor:

  udevadm monitor

Or with some older versions of udev:

  udevmonitor


Firmware Loading with Hotplug
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Hotplug is an obsolete framework for doing some of the things done by
udev today. Specifically, handling kernel hotplug events. It is used in
systems with kernel < 2.6.13 (e.g. RHEL4 / Centos4 and Debian 3.1). As
such DAHDI still installs support for those. However if you package
DAHDI for a more recent distribution, you should probably avoid
including those obsolete config files.

The relevant files installed under /etc/hotplug/usb and are
xpp/xpp_fxloader.usermap and xpp_fxloader (which is a symlink to
/usr/share/dahdi/xpp_fxloader). the usermap file has the same format as
modules.usbmap in the main kernel modules directory: it is intended to
identify a (hotplugged) device.


Loading The Modules
^^^^^^^^^^^^^^^^^^^
Here is what should happen:
In short: you should plug the Astribank device(s) or have them plugged in at
the boot time. Then all the modules should be loaded automatically.
You will see xpp_usb, xpp, and some xpd_* modules in the modules list 
(the output of lsmod).

After the module xpp is loaded, you'll also be able to see the directory
/proc/xpp. For any Astribank device discovered, you will see there a 
directory /proc/xpp/XBUS-n (where n is a number: typically 0). Once a unit have
been discovered you'll see subdirectories: /proc/xpp/XBUS-n/XPD-m (where
m may be another number: 0, 1 ,etc).

Now to the ugly details:

The driver of the Astribank is composed of several modules: 

xpp::
  The basic module, that communicates with DAHDI and provides some 
  common services to other modules.
xpd_fxs::
  FXS modules (analog phones). Module type 1.
xpd_fxo::
  FXO modules (Analog PSTN lines). Module type 2.
xpd_bri::
  BRI ("ISDN") modules. Module type 3.
xpd_pri::
  The module for controlling E1/T1 modules. Module type 4.
xpp_usb::
  The functionality needed to connect to the USB bus.

All modules depend on xpp, and modprobing them will install xpp as well.
However the xpd_* modules are installed on-demand: no need to load 
xpd_fxs if you have only Astribank FXS.

Once an Astribank device connected and the firmware is loaded, the
Vendor-ID/Product-ID of the device will be  e4e4/11x2 . The handler for that
combination is listed as the kernel module xpp_usb. Therefore, the system
runs 'modprobe xpp_usb' if that module is not already loaded.

The module xpp_usb depends on the dahdi and xpp modules. Both of them 
are loaded before xpp_usb. As usual, parameters and rules form
/etc/modprobe.conf and/or from /etc/modprobe.d/* will be applied to 
the module.

When command 'modprobe xpp_usb' returns, the span type specific modules
(e.g., xpd_fxs, xpd_fxo) may or may not have been loaded yet.

At this point the xpp driver "asks" the box about its software
(firmware) version) and the type of telephony modules it has. According 
to the answers it receives, the xpp driver will "modprobe" the required 
xpd_* modules. 

When an Astribank connects, it tells the driver what ports it has. For
instance, a system with 8BRI (=type 3) ports and 3 modules of 8FXS
(=type 1) ports:
----------------------------------------------
INFO-xpp: XBUS-00: DESCRIPTOR: 4 cards, protocol revision 30
INFO-xpp: XBUS-00:     CARD 0 type=3.0 ports=8 (2x4), port-dir=0xCC
INFO-xpp: XBUS-00:     CARD 1 type=1.0 ports=8 (8x1), port-dir=0xFF
INFO-xpp: XBUS-00:     CARD 2 type=1.0 ports=8 (8x1), port-dir=0xFF
INFO-xpp: XBUS-00:     CARD 3 type=1.0 ports=8 (8x1), port-dir=0xFF
----------------------------------------------

If dahdi, xpp or xpp_usb is missing or defective, you'll get relatively
clear error messages. However if an xpd_* module fails to load (e.g.:
because it is missing), the error is less intuitive:
--------------------------------------------------
NOTICE-xpp: xproto_get: Failed to load module for type=3. exit status=256.
NOTICE-xpp: XBUS-00: CARD 0: missing protocol table for type 3. Ignored.
--------------------------------------------------
In this case it was because I maliciously removed the module xpd_bri
(type 3) from the system.

This can also happen if you accidentally blacklist the relevant xpd-*
module. 'blacklist some_module' in modprobe.conf or modprobe.d/*.conf
means that a direct insmod or modprobe of their name will work, but any
attempt to load a module through its aliases will fail. Recall that the
cpd-* modules are loaded on-demand using the alias 'xpd-type-N' .


Device Initializations Scripts
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The chips in the device need to be initialized. This requires sending a
bunch of values to certain registers in those chips. We decided that
hardwiring those values in the driver code is not a good idea.
Before registering a XPD as a span in DAHDI, we run an initialization
script: /usr/share/dahdi/init_card_N_MM where,

* N  is telephony module type: 1 for an FXS span and 2 for an FXO span, 
  3 for BRI and 4 for PRI.
* MM - is a version number. Currently it equals 30.

Those scripts must be executable. If they are not, the initiallization
will do nothing but will give no error, and the device will work in an
unexpected way, if at all.

If because of some reasons this fails (the script is not in the place, 
or the running it produced an error), then you will get an error message 
in the logs and the XPD will then be removed (you won't see directory
for that XPD under the corresponding /proc/xpp/XBUS-* directory) and 
will not be registered with DAHDI.

As the XPD is initialized, you'll see the green LEDs of the ports steadily 
turn on and later off ("a train of lights"). This is a bit slower than the 
faster "blinking" when the XPDs register as DAHDI spans. The initialization 
of an FXS XPD may take a few seconds.


Connect / Disconnect Hook
^^^^^^^^^^^^^^^^^^^^^^^^^
When the Astribank has finished initialization it also notifies
userspace applications. This can be used to run a custom command when an
Astribank is connected (after it has finished initialization) or when it
has disconnected. The hook script is installed by default to
/usr/share/dahdi/astribank_hook .


Registering in DAHDI
^^^^^^^^^^^^^^^^^^^^
The XPDs will not automatically register as DAHDI spans. This is
intended to allow you to set the registration order (and hence the order
of DAHDI spans and channels) among multiple Astribank devices,
or between an Astribank and a different DAHDI device.

When the XPD registers with DAHDI, all the green LEDs will be lit for a
short while. 

Spans are normally registered with the utility dahdi_registration. Simply
running 'dahdi_registration' shows the available XPDs and whether or not
they are registered. To register: 

  dahdi_registration on

For a system with several spans you'll see a "fast train of lights".

If you have multiple Astribank devices, dahdi_registration will
register them by the ascending order of the USB connector ID. This
means that as long as the same Astribank is connected to the same
port, the order of plugging is not important.

You can see the USB connector ID in the verbose output of the 
dahdi_hardware utility when xpp drivers are loaded. See CONNECTOR value 
in the example below:

------------------------------------------------------
# dahdi_hardware -v
usb:004/006     xpp_usb+     e4e4:1152 Astribank-multi FPGA-firmware
 LABEL=[usb:0000148]        CONNECTOR=usb-0000:00:03.3-2
        XBUS-00/XPD-00: E1_TE    Span 1  DAHDI-SYNC
        XBUS-00/XPD-10: FXS      Span 2
        XBUS-00/XPD-20: FXS      Span 3
usb:004/007     xpp_usb+     e4e4:1152 Astribank-multi FPGA-firmware
 LABEL=[usb:0000150]        CONNECTOR=usb-0000:00:03.3-6
        XBUS-01/XPD-00: FXS      Span 4
        XBUS-01/XPD-10: FXO      Span 5
------------------------------------------------------

If you have multiple Astribank devices, dahdi_registration will register
them by the order of the "connector" field. This means that as long as
the same Astribank is connected to the same port, the order of plugging
is not important. Alternatively you can set an explicit registration
order using /etc/dahdi/xpp_order . See above in section about
<<_xpp_order_explicitly_order_astribanks,xpp_order>>.

The registration is performed through the sysfs interface. See below
<<_sys_devices_xpp_xbus_nn_nn_m_p_span,the span attribute>>. Also note 
that dahdi_registration also allows you to unregister spans, which will 
work for all spans that are not in use (That is: none of their channels 
is in use).

By default, the Astribank drivers don't perform automatic span
registration on DAHDI. It is in contrast to the all known drivers of
PCI boards. Because of that, DAHDI channels  related to the PCI board
spans will get lower numbers than the channels related to Astribank
devices.

You may choose to register the XPDs with DAHDI automatically. This may
make the startup sequence a bit simpler, but is generally not
recommended on a system with more than one Astribank or an Astribank and
a different DAHDI device. This behavior may be defined by setting
parameter <<_dahdi_autoreg>> in the modprobe configuration file (A file under
/etc/modprobe.d or /etc/modprobe.conf):

  options xpp dahdi_autoreg=1


Astribanks Synchronization Source
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
If there is more than one Astribank on the system, all the Astribanks
keep their clock in sync. Optionally the Astribanks can synchronize
their clock to the master DAHDI device (in case it is a different DAHDI
device). Normally you just use the default init.d script or run
explicitly:

  xpp_sync auto

(For now see the man page of xpp_sync for more information)


DAHDI And Above
^^^^^^^^^^^^^^^
From here you get a standard DAHDI span. The next step is to configure
the span by running the dahdi_cfg utility. You would also need to 
configure the channels in the Asterisk chan_dahdi.conf file. Only after 
that you will be able to make calls through the telephony ports.

You can use dahdi_genconf, which is included with dahdi-tools, to
generate a DAHDI and Asterisk configuration for your system.
For analog channels it works quite well, and likewise for BRI. For E1/T1 
it will probably take some tuning.

Please refer to the general DAHDI documentation for more deatils about
DAHDI and Asterisk configuration. E.g, the README file in the
top-level directory, and 

  http://voip-info.org/wiki/view/Asterisk+config+chan_dahdi.conf[]

Alternatively, write you own configuration, based on the sample from the
"Sample Configurations" section.


/proc Interface
~~~~~~~~~~~~~~~
The Astribank drivers provide their own /proc interface under /proc/xpp.
Here we review the more useful details of the procfs interface. There
are many other debugging details that are exposed through the procfs
interface. 

Also note that those details are subject to changes. Generally the
recommended stable interface are the DAHDI-perl modules and utilities 
from the xpp/ directory.


/proc/xpp/xbuses
^^^^^^^^^^^^^^^^
File /proc/xpp/xbuses lists the connected Astribank devices (one line 
per device).

A device is normally has status "connected". The status "missing" means that
the device has been disconnected, but Asterisk still holds channels from it
open.


For each Astribank device there is folder /proc/xpp/XBUS-nn and for each device
module (span in the terms of DAHDI) there is folder /proc/XBUS-nn/XPD-mm.

/proc/xpp/XBUS-nn/XPD-mm/summary 
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Contains detailed information about port statuses of the device module 
(off-hook, on-hook etc.) For example, you can run the following command
in order to monitor the port statuses in the real time:

  watch -n1 cat /proc/xpp/XBUS-00/XPD-00/summary


/proc/xpp/XBUS-nn/XPD-mm/fxo_info
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Only for FXO modules. Apart from showing the status of the LEDs, it also
shows for each FXO port if it is connected to a provider: look for the
value of "battery" for that specific port, and a bunch of other
characteristics of the port.


/proc/xpp/XBUS-nn/XPD-mm/bri_info
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
In addition to the usual information about the LEDs, this file also
provides useful information regarding ISDN Layer 1 and Layer 2 status.
For example, you can run the following command in order to monitor
the Layer 1 port statuses for all BRI devices in the real time:

  watch -n1 -d 'grep "Layer 1:" /proc/xpp/XBUS-*/XPD-*/bri_info'

For the status of the D channel of the ports on all BRI spans, run:

  watch -n1 -d 'grep D-Channel: /proc/xpp/XBUS-*/XPD-*/bri_info'


/proc/xpp/XBUS-nn/XPD-mm/pri_info
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
In addition to the usual information about the LEDs, this file also
provides useful information regarding ISDN Layer 1 and Layer 2 status.
For example, you can run the following command in order to monitor
the Layer 1 port statuses for all E1/T1 devices in the real time:

  watch -n1 -d 'grep "Layer 1:" /proc/xpp/XBUS-*/XPD-*/pri_info'

For the status of the D channel of the ports on all PRI spans, run:

  watch -n1 -d 'grep D-Channel: /proc/xpp/XBUS-*/XPD-*/pri_info'

Note: the layer 2 status is much more of a guesswork based on changes in
the contents of the channel that is supposed to be the D channel.


There are a bunch of other status files under /proc/xpp/.


/sys Interface
~~~~~~~~~~~~~~
Astribanks on the system and the xpds themselves are also represented
in SysFS. SysFS is a virtual file system mounted under /sys and provides 
information in a more structured way than ProcFS. In sysfs objects are 
represented as directories, simple attributes are shown as files in 
the directory of the object and more complex objects are subdirectories 
or symbolic links to other directories.

As with the procfs interface, we only document some interesting
attribuets. Some attributes are writable and hence writing to them
without knowing what you do is not exactly wise.

Like the procfs interface, this interface is subject to changes and
should not be considered a stable interface. Please use the DAHDI-perl
modules and utilities.


Astribanks in SysFS
^^^^^^^^^^^^^^^^^^^
Each astribank is represented as a device under
/sys/bus/astribanks/devices , with the name xbus-NN, where NN is its 
two-digit number (e.g.: 00, 01).

===== /sys/bus/astribanks/devices/xbus-NN/cls
CLear Statistics: writing to this file clear the procfs statistics for
this Astribank.

===== /sys/bus/astribanks/devices/xbus-NN/connector
Connector string for the device. The place to which the Astribank is
connected. e.g: usb-0000:00:03.3-2

===== /sys/bus/astribanks/devices/xbus-NN/label
The label string of the Astribank unit. E.g: usb:00000135

===== /sys/bus/astribanks/devices/xbus-NN/status
'connected' (normal operation) or 'disconnected' (has been disconnected,
some channels are still open).

===== /sys/bus/astribanks/devices/xbus-NN/timing
Provides some statistics in case the Astribank is not the sync source.
The format of this file is subject to future changes.

===== /sys/bus/astribanks/devices/xbus-NN/waitfor_xpds
Reading from this file only returns when the Astribank has finished
initialization of the XPDs or in case of a timeout. It prints the number
of XPDs to initialize, and the number initialize. Unless something went
wrong, those two numbers are the same. Once the span was initialized,
reading from this file returns immediately:

  XPDS_READY: XBUS-00: 3/3

===== /sys/bus/astribanks/devices/xbus-NN/xbus_state
Reading from it prints the name and number of the state of the
Astribank. This file is also writable: you can write either 'stop' to
disconnect the specific Astribank, or 'start' to reconnect it.

===== /sys/bus/astribanks/drivers/xppdrv/sync
(An attribute of the generic Astribanks driver)

The synchronization source. Normally the number of the astribank that is
the synchronization master, or 'SYNC=DAHDI' if Astribanks are
synchronized from a different DAHDI device. Normally you should just use
xpp_sync, though.

Current possible writable values:

<number>::
  Make the Astribank XBUS-<number> the sync source for other Astribanks.

DAHDI::
  Make the Astribanks synchronize with the DAHDI timing master span.
  You probably need this to get faxes from a non-Astribank adapter to an
  Astribank.


XPDs in SysFS
^^^^^^^^^^^^^
Under the Astribank you'll find a subdirectory for each of its XPDs
("spans"). The name of the directory is composed of three numbers:

<astribank>:<module>:<subunit>

astribank::
  Two-digit name of the Astribank in which this XPD is in. If it is
  xbus-03, you will see there '03'.

module::
  The number of the Astribank module: from 0 (left-most) to 3
  (right-most).

subunit::
  In a module that has several spans: the number of the span. In
  practice this is only for BRI and PRI and hence the module number will
  always be 0 in this case. 

The two-digit number of the XPD in the procfs interface is in fact
<module><subunit>.

Under this you see several attributes.

===== /sys/bus/astribanks/devices/xbus-NN/NN:M:P/blink
You can write here a number which will be considered to be a bitmask
of the ports that should blink (0 - no blinking). Reading from here
shows that bitmask. If you think that this is complicated, just use
xpp_blink.

===== /sys/bus/astribanks/devices/xbus-NN/NN:M:P/chipregs
Provides direct read/write interface to the registers of each chip. 
Reading from the file shows the result of the last read request. To make
either a read request or a write request you need to write to that file.

It is mainly used by the initialization scripts (init_card_*).

Incorrect usage of this file is one possible way of damaging the
Astribank.

===== /sys/bus/astribanks/devices/xbus-NN/NN:M:P/fxo_battery
(Only on FXO) - shows ports that have (+) or don't have (-) battery
current. That is: which ones are connected to an active FXS on the
other side.

current. That is: which ones are connected to an active FXS on the
other side.

===== /sys/bus/astribanks/devices/xbus-NN/NN:M:P/offhook
Shows ports that are (1) or are not (0) off-hook. When a channel is
not off-hook. For BRI and E1/T1 the value is 1 if the span is in use.
This value can also be used to get the number of lines (channels) in
this XPD: the count of items in this list.

===== /sys/bus/astribanks/devices/xbus-NN/NN:M:P/span
is a read/write file. Reading from it gives 0 if the span is
unregistered, or the span number if it is registered.

Writing to it allows manual registration / unregistration from DAHDI:
writing 1 registers a span (if it wasn't already registered) and writing
0 attempts to unregister it (if it is registered.  Span unregistration 
will fail if some channels from the span are used  (e.g: by Asterisk).

A more convenient interface to this is the command dahdi_registration that
registers or unregisters all the spans at once with a predefined order,
and this is what you should normally use.

Alternatively you can use the parameter dahdi_autoreg to register spans
automatically. But this is only recommended on a system with a single
Astribank and no other DAHDI device.

===== /sys/bus/astribanks/devices/xbus-NN/NN:M:P/driver
This is a standard sysfs feature: from the directory of the device you
have a link called "driver" to the directory of the driver that
handles it. One specific interesting thing is that this allows you to
easily see all the XPDs of the same type, as they are linked again
from the driver's directory.


===== /sys/bus/astribanks/devices/xbus-NN/NN:M:P/pri_protocol
Can have either of those two:

E1::
  Provides 31 channels, of which channel 16 is normally the D-channel. 
  Common in places outside of North America and Japan. This is the 
  default setup.

T1::
  T1 provides 24 channels. The last one is normally the D-Channel.
  Common in North America.

This can also be set by writing the strings explicitly to the file. But
can only be done when an XPD is not a registered span.

This writing is normally done by the device initialization script, based
on the 'pri_protocol' settings in 
xref:_xpp_conf_astribank_initialization[/etc/dahdi/xpp.conf] .


Useful Module Parameters
~~~~~~~~~~~~~~~~~~~~~~~~
Compilation-time defaults for the all modules can be shown as part of the
description line for the parameter in the "modinfo" command output.

==== dahdi_autoreg
(xpp)

Register spans automatically (1) or not (0). Default: 0. 
Setting it simplifies operations with a single Astribank and no other 
DAHDI hardware. However if you have such systems, automatic
registration can cause the order of spans to be unpredictable.
The standard startup scripts use 'dahdi_registration on' instead of this.

==== initdir
(xpp)

This is the directory containing the initialization scripts.
The default is /usr/share/dahdi .
Setting this value could be useful if that location is inconvenient for you.

==== rx_tasklet
(xpp)

Enable (1) or disable (0) doing most of the packets processing in
separate tasklets. This should probably help on higher-end systems with
multiple Astribanks.

==== debug
(all modules)

It will make the driver to print tons of debugging messages. You can 
set/unset the parameter at run-time. The parameter value is a bitmask 
of several values. The different bits  meaning as it defined in 
xpp/dahdi_debug.h: 

* 0  - Disable debug messages
* 1  - GENERAL - General debug comments.
* 2  - PCM - PCM-related messages. Tends to flood logs.
* 4  - LEDS - Anything related to the LEDs status control. The driver
       produces a lot of messages when the option is enabled.
* 8  - SYNC - Synchronization related messages.
* 16 - SIGNAL - DAHDI signalling related messages.
* 32 - PROC - Messages related to the procfs interface.
* 64 - REGS - Reading and writing to chip registers. Tends to flood
	 logs.
* 128 - DEVICES - Device instantiation, destruction and such.
* 256 - COMMANDS - Protocol commands. Tends to flood logs.

For example,

  echo 33 >/sys/modules/xpp/parameters/debug 

forces module xpp to print general debugging messages (1) and procfs
debugging messages (32).

==== vmwi_ioctl
(xpd_fxs)

Does userspace support VMWI notification via ioctl? Default: 1 (yes).

Disable this (0) to have the driver attempt to detect the voicemail
message waiting indication status for this port from FSK messages
userspace (Asterisk) sends. Set the ports to use AC neon-lamp style
message waiting indication. The detection from the FSK messages takes
extra CPU cycles but is required with e.g. Asterisk 1.4.x .

Also note that in order for this parameter to take effect, it must be
set before the span is registered. This practically means that it
should be set through modprobe.d files.

See also <<_voicemail_indication,Voicemail Indication>>.

==== usb1
(xpp_usb)

Enable (1) or disable (0) support of USB1 devices. Disabled by default.

USB1 devices are not well-tested. It seems that they don't work at all
for Astribank BRI. Generally they should work with the current code, but
we expect the voice quality issues. Hence we would like to make it
very clear that you if you have a USB1 port (rather than a USB2 one, as 
recommended) you will have to take an action to enable the device.

==== poll intervals 
(various)

There are various values which the driver occasionally polls the
device for. For instance, the parameter poll_battery_interval for
xpd_fxo to poll the battery, in order to know if the telco line is
actually connected.

The value of those parameters is typically a number in milliseconds. 
0 is used to disable polling. Under normal operation there should be 
no reason to play with those parameters.

==== dtmf_detection
(xpd_fxs)

Enable (1) or disable (0) support of hardware DTMF detection by the 
Astribank.

==== caller_id_style
(xpd_fxo)

Various types of caller ID signalling styles require knowing the PCM
even when the line is on-hook (which is usually a waste of CPU and
bandwidth). This parameter allows fine-tuning the behaviour here:

* 0 (default) - Don't pass extra PCM when on-hook.
* 1 ETSI-FSK: Wait for polarity reversal to come before a ring and 
  then start passing PCM until the caller ID has been passed.
* 2 Always: Always pass PCM.

This parameter is read-only. It cannot be changed at run-time.

==== battery_threshold
(xpd_fxo)

Minimum voltage that shows there is battery. Defaults to 3. Normally you
should not need to change this, unless dealing with a funky PSTN
provider.

==== battery_debounce
(xpd_fxo)

Minimum interval (msec) for detection of battery off (as opposed to e.g.
a temporary power denial to signal a hangup). Defaults to 1000. As with
battery_threshold above, there's normally no need to tweak it.


NOTE: XPP here does not stand for X Printing Panel, XML Pull Parser, 
X-Windows Phase Plane or XML Professional Publisher. It is simply the 
Xorcom Peripheral Protocol, which connects a computer to a XPD (Xorcom 
Peripheral Device). An XBUS (originally XPP Bus) is actually a single
Astribank device and the XPDs have become the single modules in it.
