I have talked about this radio back in the day. Please See NexGen Simulator Blog Index iii. You will see 13 prior entries. So why 14? This post is using my current schematic for the wiring which will do the decoding very straightforward.  The C-3426A schematics and pinouts are included in  TM 11-5826-215-35, "Field and Depot Maintenance Manual Receiving Set Radio AN/ARN-30D", (page 15). As you can see below the data from the head is from ARC-158115 (19pins) which is connected to DB25.1 and its pin for pin. easy peasy.  The second connector ARC-14050 is an 8 pin connector that is connected to DB25.2 This connector has panel lamps, volume, and power switch. The pins from the third ARC Connector, ARC-18250 are not required. Even though They are on the DB25.2 I will be ignoring them.

The CANaerospace specification states that my datatype can be ACARH4 witch are 4 ASCII chars, this should be called  2x 2 Hexadecimal values. My datatype Number is 0x100 which is in the User Defined datatypes.

H0H1H2H301234567

NODE

ID

DATATYPESERVICE CODEMESSAGE CODEM/KUpper valueslower values
11040x1000-255M7H5F

So if my radio was tuned to 126.95  Mhz I would call 0xvalue = tohex (number), twice. and therefor 7h = tohex (126) and  5f = tohex (95 ) and the MK field would get an M (Mhz).

Its Node-Id = 1104 (this value is pre-assigned for the most part, see page 43, in the book "NASA AGATE data bus, Interface specification for Airborne CAN applications".

 

 

The Plan:

Now that some of the how-to stuff is out of the way.

  • It is time to build a red box for the radio, install the radio and the CAN module along with the dual RJ-45 board, and wire the Arduino to DB-25.1 power it up and test it via the USB port.
  • At this time if all goes well I will wire DB-25.2 for the ARC-14050 connector to the Arduino. The next major hurdles are to integrate the two CAN modules and see if I can pass data between the two boxes at that time the Protocol Converter will only be acting as node-0 or a local controller.
  • One of the last tests is to see if I can interrogate my  Radio from my Controller and see if the Radio responds with a correct status message