Provided by: libhamlib-utils_4.3.1-1build2_amd64 bug


       ampctld - TCP amplifier control daemon


       ampctld [-hlLuV] [-m id] [-r device] [-s baud] [-T IPADDR] [-t number] [-C parm=val]


       The ampctld program is an amplifier control daemon that handles client  requests  via  TCP
       sockets.   This  allows  multiple  user  programs  to share one amplifier (this needs more
       development).  Multiple amplifiers can be controlled on different  TCP  ports  by  use  of
       multiple ampctld processes.  Note that multiple processes/ports are also necessary if some
       clients use extended responses and/or vfo mode.  So up to 4 processes/ports may be  needed
       for  each  combination  of extended response/vfo mode.  The syntax of the commands are the
       same as ampctl(1).  It is hoped that ampctld will be especially useful for client  authors
       using languages such as Perl, Python, PHP, and others.

       ampctld  communicates  to  a  client  through a TCP socket using text commands shared with
       ampctl.  The protocol is simple, commands are sent to ampctld  on  one  line  and  ampctld
       responds  to  get  commands  with  the  requested  values,  one per line, when successful,
       otherwise, it responds with one line “RPRT x”, where ‘x’ is a negative  number  indicating
       the  error code.  Commands that do not return values respond with the line “RPRT x”, where
       ‘x’ is ‘0’ when successful, otherwise is a regative  number  indicating  the  error  code.
       Each line is terminated with a newline ‘\n’ character.  This protocol is primarily for use
       by the NET ampctl (amplifier model 2) backend.

       A separate Extended Response Protocol extends the above behavior by echoing  the  received
       command  string  as  a  header, any returned values as a key: value pair, and the “RPRT x”
       string as the end of response marker which includes the Hamlib success or  failure  value.
       See  the PROTOCOL section for details.  Consider using this protocol for clients that will
       interact with ampctld directly through a TCP socket.

       Keep in mind that Hamlib is BETA level software.  While a lot of  backend  libraries  lack
       complete amplifier support, the basic functions are usually well supported.

       Please  report  bugs  and provide feedback at the e-mail address given in the BUGS section
       below.  Patches and code enhancements sent to the same address are welcome.


       This program follows the usual GNU command  line  syntax.   Short  options  that  take  an
       argument  may  have the value follow immediately or be separated by a space.  Long options
       starting with two dashes (‘-’) require an ‘=’ between the option and any argument.

       Here is a summary of the supported options:

       -m, --model=id
              Select amplifier model number.

              See model list (use “ampctl -l”).

              Note: ampctl (or third party software using the C API) will use amplifier  model  2
              for NET ampctl (communicating with ampctld).

       -r, --amp-file=device
              Use device as the file name of the port connected to the amplifier.

              Often  a  serial port, but could be a USB to serial adapter.  Typically /dev/ttyS0,
              /dev/ttyS1, /dev/ttyUSB0, etc. on Linux, COM1, COM2, etc. on MS Windows.   The  BSD
              flavors and Mac OS/X have their own designations.  See your system's documentation.

       -s, --serial-speed=baud
              Set serial speed to baud rate.

              Uses  maximum serial speed from amplifier backend capabilities (set by -m above) as
              the default.

       -t, --port=number
              Use number as the TCP listening port.

              The default is 4531.

              Note: As rigctld's default port is 4532 and rotctld's default port is 4533,  it  is
              recommended  to  use  DESCENDING odd numbered ports for multiple ampctld instances,
              e.g. 4529, 4527, 4525, etc.

       -T, --listen-addr=IPADDR
              Use IPADDR as the listening IP address.

              The default is ANY.

       -L, --show-conf
              List all config parameters for the amplifier defined with -m above.

       -C, --set-conf=parm=val[,parm=val]
              Set amplifier configuration parameter(s), e.g.  stop_bits=2.

              Use the -L option above for a list of configuration parameters for  a  given  model

       -u, --dump-caps
              Dump capabilities for the amplifier defined with -m above and exit.

       -l, --list
              List all amplifier model numbers defined in Hamlib and exit.

              The list is sorted by model number.

              Note:  In Linux the list can be scrolled back using Shift-PageUp/Shift-PageDown, or
              using the scrollbars of a virtual terminal in X or the cmd window in Windows.   The
              output can be piped to more(1) or less(1), e.g. “ampctl -l | more”.

       -v, --verbose
              Set verbose mode, cumulative (see DIAGNOSTICS below).

       -Z, --debug-time-stamps
              Enable time stamps for the debug messages.

              Use only in combination with the -v option as it generates no output on its own.

       -h, --help
              Show a summary of these options and exit.

       -V, --version
              Show version of ampctl and exit.

       Note:  Some  options  may  not be implemented by a given backend and will return an error.
       This is most likely to occur with the --set-conf and --show-conf options.

       Please note that the backend for the amplifier to be controlled, or the  amplifier  itself
       may  not support some commands.  In that case, the operation will fail with a Hamlib error


       Commands can be sent over the TCP socket either as a single char, or  as  a  long  command
       name plus the value(s) space separated on one ‘\n’ terminated line. See PROTOCOL.

       Since most of the Hamlib operations have a set and a get method, an upper case letter will
       be used for set methods whereas the corresponding lower case  letter  refers  to  the  get
       method.   Each  operation  also  has a long name; prepend a backslash, ‘\’, to send a long
       command name.

       Example (Perl): “print $socket "\\dump_caps\n";” to see what the amplifier's  backend  can
       do  (Note: In Perl and many other languages a ‘\’ will need to be escaped with a preceding
       ‘\’ so that even though two backslash characters appear in the  code,  only  one  will  be
       passed to ampctld.  This is a possible bug, beware!).

       Note:  The  backend  for  the  amplifier to be controlled, or the amplifier itself may not
       support some commands. In that case, the operation will fail with a Hamlib error message.

       Here is a summary of the supported commands (In  the  case  of  set  commands  the  quoted
       italicized  string  is  replaced  by  the  value  in  the description.  In the case of get
       commands the quoted italicized string is the key name of the value returned.):

       F, set_freq 'Frequency'
              Set 'Frequency', in Hz.

              Frequency may be a floating point or integer value.

       f, get_freq
              Get 'Frequency', in Hz.

              Returns an integer value.

       l, get_level 'Level'
              Get 'Level Value'.

              Returns Level Value as a float or integer for the Level token given.

              Note: Passing a ‘?’ (query) as the first argument instead of  a  Level  token  will
              return a space separated list of amplifier backend supported get level tokens.  Use
              this to determine the supported levels of a given amplifier backend.

              Return certain state information about the amplifier backend.

       1, dump_caps
              Not a real amplifier remote command, it just  dumps  capabilities,  i.e.  what  the
              backend knows about this model, and what it can do.

              TODO:  Ensure  this  is  in  a  consistent  format  so  it can be read into a hash,
              dictionary, etc.  Bug reports requested.

              Note: This command will produce many lines of output so be very careful if using  a
              fixed  length  array!   For example, running this command against the Dummy backend
              results in a number of lines of text output.

       _, get_info
              Return information from the amplifier backend.

       R, reset 'Reset'
              Perform amplifier 'Reset'.

              Reset is an integer value: ‘0’ = None, ‘1’ = Memory reset, ‘2’ = Fault reset, ‘3’ =
              Amplifier reset.

       set_powerstat 'Power Status'
              Set 'Power Status'.

              Power  Status  is  an  integer  value: ‘0’ = Power Off, ‘1’ = Power On, ‘2’ = Power
              Standby (enter standby), ‘4’ = Power Operate (leave standby).

              Get 'Power Status' as in set_powerstat above.


       There are two protocols in use by ampctld, the Default Protocol and the Extended  Response

       The  Default  Protocol  is intended primarily for the communication between Hamlib library
       functions and ampctld (“NET ampctl”, available using amplifier model ‘2’).

       The Extended Response Protocol is intended to be  used  with  scripts  or  other  programs
       interacting directly with ampctld as consistent feedback is provided.

   Default Protocol
       The  Default Protocol is intentionally simple.  Commands are entered on a single line with
       any needed values.  In practice, reliable results are obtained by terminating each command
       string with a newline character, ‘\n’.

       Example set frequency and mode commands (Perl code (typed text shown in bold)):

           print $socket "F 14250000\n";
           print $socket "\\set_powerstat 1\n"; # escape leading '\'

       A  one  line  response  will be sent as a reply to set commands, “RPRT x\n” where x is the
       Hamlib error code with ‘0’ indicating success of the command.

       Responses from ampctld get commands are text values and match the same tokens used in  the
       set  commands.  Each value is returned on its own line.  On error the string “RPRT x\n” is
       returned where x is the Hamlib error code.

       Example get frequency (Perl code):

           print $socket "f\n";

       Most get functions return one to three  values.  A  notable  exception  is  the  dump_caps
       command which returns many lines of key:value pairs.

       This  protocol is primarily used by the “NET ampctl” (ampctl model 2) backend which allows
       applications already written for Hamlib's C API to take advantage of ampctld  without  the
       need  of  rewriting  application code.  An application's user can select amplifier model 2
       (“NET ampctl”) and then set amp_pathname to “localhost:4531” or  other  network  host:port
       (set by the -T/-t options, respectively, above).

   Extended Response Protocol
       The  Extended  Response protocol adds several rules to the strings returned by ampctld and
       adds a rule for the command syntax.

       1. The command received by ampctld is echoed with its long command name  followed  by  the
       value(s)  (if any) received from the client terminated by the specified response separator
       as the first record of the response.

       2. The last record of each block is the string “RPRT x\n” where x is  the  numeric  return
       value of the Hamlib backend function that was called by the command.

       3.  Any  records consisting of data values returned by the amplifier backend are prepended
       by a string immediately followed by a colon then a space and then the value terminated  by
       the  response  separator.  e.g.  “Frequency: 14250000\n” when the command was prepended by

       4. All commands received will be acknowledged by ampctld
        with records from rules 1 and 2.  Records from rule 3 are only returned when data  values
       must be returned to the client.

       4.  All commands received will be acknowledged by ampctld with records from rules 1 and 2.
       Records from rule 3 are only returned when data values must be returned to the client.

       An example response to a set_frequency command  sent  from  the  shell  prompt  (note  the
       prepended ‘+’):

           $ echo "+F 14250000" | nc -w 1 localhost 4531
           set_freq: 14250000
           RPRT 0

       In  this  case  the  long  command  name and values are returned on the first line and the
       second line contains the end of block marker and  the  numeric  amplifier  backend  return
       value indicating success.

       An example response to a get_freq query:

           $ echo "+\get_freq" | nc -w 1 localhost 4531
           Frequency(Hz): 14250000
           RPRT 0

              Note:  The  ‘\’  is  still  required  for  the  long command name even with the ERP

       In this case, as no value is passed to ampctld, the first line consists only of  the  long
       command  name.   The  final  line shows that the command was processed successfully by the
       amplifier backend.

       Invoking the Extended Response Protocol requires prepending a command with  a  punctuation
       character.   As  shown  in  the  examples above, prepending a ‘+’ character to the command
       results in the responses being  separated  by  a  newline  character  (‘\n’).   Any  other
       punctuation  character recognized by the C ispunct() function except ‘\’, ‘?’, or ‘_’ will
       cause that character to become the response separator and the entire response will  be  on
       one line.

       Separator character summary:

       ‘+’    Each record of the response is appended with a newline (‘\n’).

       ‘;’, ‘|’, or, ‘,’
              Each  record of the response is appended by the given character resulting in entire
              response on one line.

              These are common record separators for text representations  of  spreadsheet  data,

       ‘?’    Reserved for help in ampctl.

       ‘_’    Reserved for get_info short command

       ‘#’    Reserved for comments when reading a command file script.

              Note: Other punctuation characters have not been tested!  Use at your own risk.

       For example, invoking a get_freq query with a leading ‘;’ returns:

           get_freq:;Frequency(Hz): 14250000;RPRT 0

       Or, using the pipe character ‘|’ returns:

           get_freq:|Frequency(Hz): 14250000|RPRT 0

       And a set_freq command prepended with a ‘|’ returns:

           set_freq: 14250000|RPRT 0

       Such  a  format will allow reading a response as a single event using a preferred response
       separator.  Other punctuation characters have not been tested!


       The -v, --verbose option allows different levels of diagnostics to be output to stderr and
       correspond  to  -v  for  BUG, -vv for ERR, -vvv for WARN, -vvvv for VERBOSE, or -vvvvv for

       A given verbose level is useful for providing needed debugging information  to  the  email
       address  below.   For  example,  TRACE output shows all of the values sent to and received
       from the amplifier which is very useful for amplifier backend library development and  may
       be requested by the developers.


       Start ampctld for an Elecraft KPA-1500 using a USB-to-serial adapter and backgrounding:

           $ ampctld -m 201 -r /dev/ttyUSB1 &

       Start ampctld for an Elecraft KPA-1500 using COM2 on MS Windows:

           $ ampctld -m 201 -r COM2

       Connect to the already running ampctld and set the frequency to 14.266 MHz with a 1 second
       read timeout using the default protocol from the shell prompt:

           $ echo "\set_freq 14266000" | nc -w 1 localhost 4531

       Connect to a running ampctld with ampctl on the local host:

           $ ampctl -m2


       No authentication whatsoever; DO NOT leave this  TCP  port  open  wide  to  the  Internet.
       Please  ask  if  stronger  security  is  needed  or consider using a Secure Shell (ssh(1))

       As ampctld does not need any greater permissions than ampctl, it is advisable to not start
       ampctld as “root” or another system user account in order to limit any vulnerability.


       The daemon is not detaching and backgrounding itself.

       No method to exit the daemon so the kill(1) command must be used to terminate it.

       Multiple clients using the daemon may experience contention with the connected amplifier.

       Report bugs to:

              Hamlib Developer mailing list


       This  file  is  part  of  Hamlib,  a  project  to develop a library that simplifies radio,
       rotator, and amplifier control functions for developers of software primarily of  interest
       to radio amateurs and those interested in radio communications.

       Copyright © 2000-2010 Stephane Fillod
       Copyright © 2000-2018 the Hamlib Group (various contributors)
       Copyright © 2011-2020 Nate Bargmann

       This is free software; see the file COPYING for copying conditions.  There is NO warranty;


       kill(1), ampctl(1), ssh(1), hamlib(7)


       Links to the Hamlib Wiki, Git repository, release archives, and  daily  snapshot  archives
       are available via ⟨⟩.