Tuesday, February 2, 2016

Programming the ICOM M710 with DIY CI-V

Success and failure...USB-TTL to ICOM M710 programming cable

I need to reprogram my I-COM M710 Marine SSB/HAM HF rig. I have been using it aboard my sailboat since it was new in 2006 with an older Pactor IIe.

I would like to play with WinMOR and soundcard modem and some of the digital modes.

I searched the Internet and found most people were making (8 years ago) clones of the ICOM interface OPC-478.

So I first made clone cable like the CI-V cable  with  dual 2N2222s, a diode, some resisters and a DB9 connector. It needed to be plugged into my current laptop with a USB-serial adapter/emulator.  It failed. I must have put a transistor in backwards or something. Then I found the ICOM software. The software for cloning and configuring the M710 seems to be EX1726.exe (for 710RT use ES2144.exe) for DOS. It does direct manipulation of the serial port register so a PC with an real DB9 serial port running DOS, not Windows, would be required. I do not have these.

I kept searching.

I next found web page that says the ICOM clone port is TTL open collector, just one wire. And also elsewhere found the clause, "NMEA 0183 sentences at 4800 baud".

And a note describing how to make a clone cable from a USB-TTL adapter, commonly used to program Arduinos, and a phone plug.

   connect tip of mono phone plug to Rx and Tx soldered together and ring to ground of a USB to TTL serial adapter. I used a PL2303 based 5 pin adapter.

Mine shows up in syslog as:

Feb 2 14:50:18 nav3 kernel: [27157.768171] usb 1-4.4: Manufacturer: Prolific Technology Inc.
Feb 2 14:50:18 nav3 kernel: [27157.768585] pl2303 1-4.4:1.0: pl2303 converter detected

The user  belizesailor at Cruiser Forum says the DosBox emulator for games emulates the serial port so well that the ICOM software will work.

OK! I quickly made the cable for the USB-TTL adapter in the photo. Then downloaded DosBox from www.dosbox.com, for debian to my ubuntu 15.10 system.

I actually used the synaptic package manager and checked the box to include dependent packages from the repository. It worked fine. All this after a failed attempt to download the source tar ball and compile it myself. And I had also tried to install the packages on WinXP, but I have no XP driver for the Prolific USB.

Then found EX1726.zip at http://ea4yx.jimdo.com/software-radioaficionados/control-equipos/software-icom/

After unzip'ing it, edit the config file ~/.dosbox/dosbox-0.74.conf
 to set the serial ports to emulate, these two lines:
serial1=directserial realport:ttyUSB0
serial2=directserial realport:ttyUSB1

So to program the M710 from Ubuntu-Gnome 15.10, select:
Menu> Games> DosBox

Then in DosBox:

Z:\> mount c ~/Data/Radio/EX1726

Z:\> C:

c:\>  ex1726 /expert       # see the README maybe called M710.DOC

ESC > Clone > Rs232 >port2    # ttyUSB1

ESC > C > T   # read from transceiver to PC



  1. Can you share me , about detail interface cable ICOM M710

  2. direct email me at larryl at tcls dot com with more details about your question.