icom - Program to Control ICOM Receivers and Transceivers
icom [-r radio] [-c
channel] [-m mode] [-o
offset] [-g frequency] [-d] [-k]
[-f file]
This program can be used to control ICOM radio receivers and transceivers with the CI-V option. Most recent ICOM radios already have this option; older radios can be converted with an appropriate adapter mounted inside the radio. The program implements a virtual radio with from 32 to 101 channels corresponding to the memory channels implemented in the particular radio model. Each channel can hold a frequency, mode and, in some radios, a transmit duplex offset (VHF/UHF FM radios only). Most radios support USB, LSB, AM, CW and RTTY modes. Some radios support narrow/wide filters and some support FM modes as well. Additional features that can be controlled on some radios are antenna selection, scan control and tuning step.
The program implements a virtual radio with a bank of memory channels and two VFOs, one corresponding to the main receiver and the other corresponding to the secondary receiver in some radios. The radio is controlled by commands entered from the keyboard or keypad. In these commands, the command name and arguments are case-insensitive. The main VFO frequency, mode and offset is controlled directly by the program. The secondary VFO is controlled by loading from, or exchanging contents with, the main VFO. Commands are provided to select other memory channels and to write the current VFO data to a memory channel.
The program can be controlled in three ways: batch mode, keyboard mode, and keypad mode. In keyboard mode, commands and arguments are entered from the main keyboard following the "icom>" prompt, one command per line, and the complete command set is available. In batch mode, the same commands and arguments are read from the file specified as an option in the command line that starts the program. In keypad mode, commands and arguments are entered from the numeric keypad following the ">" prompt. In this mode, most routine keystrokes use the numeric keypad to enter arguments, and the arguments are followed by a single character representing the command name.
Options on the command line that starts the program can be used to
select the radio model and set the frequency and mode. Using a suitably
crafted crontab file, it is possible to tune a radio to
different frequencies used by a shortwave broadcaster throughout the
day, for example. With the minimuf program (available in a
separate distribution), it is possible to build shell scripts that
predict the most likely frequencies and tune the radio as well.
The program knows about the following radios and modes. New radios
can be added to the name[] vector defined in the radio.c
file.
Name Description ID Modes -------------------------------------------------------- 271 VHF Transceiver 20 LSB, USB, CW, FM 275 VHF Transceiver 10 LSB, USB, CW, FM 375 VHF Transceiver 12 LSB, USB, CW, FM 471 UHF Transceiver 22 LSB, USB, CW, FM 475 UHF Transceiver 14 LSB, USB, CW, FM 575 VHF Transceiver 16 LSB, USB, CW, FM 725 HF Transceiver 04 LSB, USB, CW, AM, *FM 735 HF Transceiver 28 LSB, USB, CW, AM, *FM 751 HF Transceiver 1c LSB, USB, CW, AM, *FM 761 HF Transceiver 1e LSB, USB, CW+, RTTY+, AM+, FM 775 HF Transceiver 46 LSB+, USB+, CW+, RTTY+, AM+, FM 781 HF Transceiver 26 LSB+, USB+, CW+, RTTY+, AM+, FM 1271 UHF Transceiver 24 LSB, USB, CW, FM R71A HF Receiver 1a LSB, USB, CW, RTTY, AM, *FM R72A HF Receiver 32 USB, LSB, CW+, RTTY+, AM+, *FM R7000 VHF/UHF Receiver 08 USB, AM, FM+
Notes: Those radios marked *FM require an optional accessory to receive FM. A plus sign (+) following a mode indicates filters can be selected for wide (w suffix) or narrow (n suffix). Not all radios support all filter combinations. For the R7000, USB selects the radio SSB mode, FMw the radio FM (wideband-FM) mode and FM selects the radio FMn (narrowband-FM) mode. The upper/lower sideband is selected by a switch on the back of the radio. This list has been confirmed only for the 271, 761, 775, R71A, R72A and R7000 radios.
Most commands and command line options take arguments, although many arguments can be defaulted. Arguments specified as frequency are in fixed-point format in MHz, if less than 1000, and in kHz otherwise. Arguments specified as offset are in fixed-point format in kHz. Arguments specified as step are in integer format in Hz. Arguments specified as mode, take names listed in the above table for the various radios. Note that these names are used consistently; that is, the narrowband FM mode on the 271 corresponds to the narrowband FM mode on an R7000, in spite of the fact the radio controls are labelled differently. Arguments specified as channel refer to any valid memory channel number available in the particular radio. A channel number specified as '.' means the currently selected channel and '$' the highest channel available.
The program exits when command line options are processed and the
command line includes any option other than -r, -
i or -f. This is designed for use in shell scripts
where all functions can be completed using only command line options.
Keyboard mode is signalled by the prefix icom>, while
keypad mode is signalled by the prefix >. Keyboard and
batch commands are terminated by a Enter key on either the
keyboard or numeric keypad. Keypad commands are terminated by a special
character depending on the command.
A radio must be selected before any command which controls the radio.
This can be done using the radio command in either keyboard
or batch modes and the -r command line option. The radio
cannot be selected in the keypad mode. The radio command
can be used at any time to reselect a different radio. The
chan command selects the memory channel to use and displays
the frequency, mode (and transmit duplex offset where available) stored
in that channel. The freq command sets the VFO frequency
and optional mode, but does not actually write the memory channel.
Likewise, the mode command sets the mode without affecting
the frequency. For VHF/UHF radios, the duplex command sets
the transmit duplex offset; however, at least with the 271, there
appears no obvious means to set the sign of this offset. The
write command writes the frequency, mode and offset
information to the memory channel, destroying its prior contents. The
clear command clears the memory channel for those radios
that support it. For those radios that have a secondary (SUB) receiver,
e.g., 775, the split command sets the transmit offset, but
this cannot be stored in a memory channel.
Most ICOM HF radios tune in 10-Hz steps, while VHF/UHF radios tune in
100-Hz steps for USB/LSB and 15 kHz for AM/FM. The step
command can be used to change the default tuning step. Some ICOM radios
do not compensate the LO when the mode is changed and the BFO shifted to
adjust the passband. This has the effect of detuning the radio by an
amount up to 3 kHz, depending on mode. With these radios, the
freq command can be used with optional mode argument, in
which case the program rewrites the frequency after the mode is set. In
the case of transceivers with general-coverage receivers, care should be
given to the setting of the GENE-HAM switch. If in the HAM position, it
is not possible to change to a frequency outside the ham bands. Since
the setting of this switch is saved along with the frequency and mode in
a channel and apparently cannot be changed using radio commands, the
setting may have to be done manually.
The keyboard mode can be very awkward when searching a band for
signals, since a new freq command must be used every time
the frequency is changed. The keypad command puts the
program in keypad mode and changes the prompt string to ">". In this
mode, arguments such as frequency, tuning step, etc., can be entered
directly from the keypad. Of course, the keypad must be in Num
Lock mode for this to work properly. In keypad mode, the
arguments are given first followed by a single character which
identifies the command and terminates input.
The easiest way to tune the radio is using the +,
-, ENTER, . and digit keys. The
frequency is entered directly using the . and digit keys
and terminated with the ENTER key. The + and
- keys tune up and down the default tuning step selected by
the keypad s command; or, if a number is entered prior to
the + or - key, that number in Hz replaces the
default just for that command. If the ENTER key is pressed
with no preceding digits, the current frequency, mode and offset are
displayed. With a little practice, it is easy to scan a band (say with
1-kHz steps in USB) looking for signals and, when one is found, change
to 100-Hz steps to move closer and then to 10-Hz steps for the final
adjustment. With more practice, the final adjustment can be reached with
fewer keystrokes by specifying a step in Hz preceding the +
or - keys.
When using this program to operate more than one radio that covers
the same frequency bands and modes, it may be useful to use a standard
set of files, which could be loaded into any of the radios directly from
the file. The program includes the capability to save and restore a
block of memory channels to and from a file using the save
and restore commands. This allows channel blocks to be
created by other programs and copied from one radio to another, for
example. The information saved in the file includes the frequency, mode
and offset. The program can also execute a list of commands stored in a
file and interpreted in batch mode.
However, it often happens that individual radios need slightly different
frequency settings to receive the same frequency transmission,
especially when narrow filters are in use. A common example is when
selecting from a standard set of frequencies using the
minimuf program (described elsewhere) and a Unix
cron to automatically tune the radio(s) throughout the day.
The keyboard offset command and -o command
line option preset a constant frequency offset value to be added to
subsequent frequency values as they are transmitted to the radio.
Usually, the offset is characteristic of the radio, as the result of BFO
frequency error, for example, and can be calibrated manually in advance.
Batch mode is designed for cases where a number of radios are to be cloned or programmed with memory channel data produced by another program. In principle, a Unix shell script could search an archive for the current VOA transmission schedules and transmitter locations, another program determine the propagation model and best frequencies for the receiver location and current time of day, and then program the radio(s) with the results.
The program communicates with one or more radios using the CI-V broadcast bus and serial asynchronous protocol. The CT-17 level converter can be used to interface the CI-V voltage levels (TTL) to EIA (RS-232) levels, or a homebrew unit can be made from the MAX232 IC plus a handful of capacitors. The CT-17 supports up to four radios, but there is no inherent protocol limitation to this number. The CI-V uses active- low drivers with resistor pullups, so multiple radios can be connected to the same wire.
Messages are exchanged in the form of frames beginning with two preamble bytes (0xfe) and ending with one end of message byte (0xfd). In order to handle the older radios, the control program operates at 1200 bps; however, it can be compiled to operate at higher speeds. Each radio model is assigned a unique identifier byte, which can be changed if necessary. The control program sends a frame with that identifier and expects a reply, either containing data or a single ACK (0xfb) or NAK (0xfa). Most functions implemented by the control program require an exchange of several frames.
It has been the experience that some radios can occasionally fail to respond to a command or respond with a mangled frame. Therefore, the control program includes a good deal of error-recovery code and uses timeouts and retransmissions as necessary. Since the CI-V bus uses a broadcast architecture, every octet transmitted by the control program is read back and checked. If the readback fails or no reply is received after three retransmissions, the operation fails and an error message is displayed.
Following is a list of recognized command line options. Note that, in
the case of multiple options, they should be in the order -r, -c,
-m, -o, -g, -d, -k and -f.
-r name
-c channel
-m mode
-o offset
-g option to
offset kHz.
-g frequency
-d
-k
-f filename
Following is a list of commands recognized in keyboard and batch
modes. Note that the radio command must be given before any
command, other than debug or quit. Other than
this, there are no restrictions on the order of these commands. The
commands recognized in batch mode are any that are recognized in
keyboard mode, except the pad command, which puts the
program in keypad mode.
ant [ antenna ]
chan [ channel ]
c command and the channel selection buttons or knobs on the
radio.
clear [ channel ]
x command and the CLEAR button on
the radio.
debug level
down [ step ]
tune
keyboard command or keypad t command. This is the same
function as the keypad - command.
duplex [ offset ]
+-DUPLEX
switch.
equal
= command and the
EQUAL button on the radio. Note: This command works only in
split or watch modes.
freq frequency [ mode
]
offset command, and optional
mode. Note: In some ICOM radios it is not possible to set the
frequency of the last channel less than that of the next-to-last
channel. Presumably, this is to avoid abusing the internal scan feature
of the radio.
mode [ mode ]
offset [ offset ]
freq commands to
offset kHz.
quit
radio [ name ]
restore file [ first
] [ last ]
save file [ first ]
[ last ]
split [ split ]
s
command.
step [ step ]
up
and down keyboard commands and + and -
keypad commands to step. If step is missing, use
the standard tuning step of the radio. This is the same function as the
keypad s command.
swap
swap
command and the CHANGE button on the radio. Note: This
command works only in split or watch modes.
up [ step ]
tune command or keypad t command. This is the
same function as the keypad + command.
watch [ON | OFF]
ON or OFF. If
missing, set the function OFF.
write [ channel ]
w command
and the WRITE button on the radio.
Following is a list of commands recognized in keypad mode. There are no restrictions on the order of these commands.
#
[step]+
tune command or keypad t command. This is the
same function as the keyboard up command.
[step]-
tune command or keypad t command. This is the
same function as the keyboard down command.
/
swap
command and the CHANGE button on the radio. Note: This
command works only in split or watch modes.
=
equal command and
the EQUAL button on the radio. Note: This command works
only in split or watch modes.
a
[channel]c
chan keyboard command and the channel selection buttons or
knobs on the radio.
[frequency]f
Enter key on the keypad or keyboard can be used as a
shortcut for the f keyboard key. If frequency is
missing, the current frequency, mode and offset are displayed.
m
q
[split]s
split command.
[step]t
up
and down keyboard commands and + and -
keypad commands to step. If step is missing, use
the standard tuning step of the radio. This is the same function as the
keyboard step command.
[channel]w
write
command and the WRITE button on the radio.
[channel]x
clear command and the CLEAR
button on the radio.
Written by David L. Mills, W3HCF; this update 25 September 1996.
This is a work in progress. Many idiosyncrasies of various ICOM radios remain to be discovered.