Ok, definitely start by reading pp. 3-6 of the document MED posted. This explains the format of the 3-byte TMCC command strings.
The function I wrote takes these parameters:
sendTMCCCommand (SysTypes deviceType, byte deviceID, byte commandField, byte dataField, byte repeats)
For your example (blowing a horn on a TMCC engine)
- deviceTYPE = ENGType (B00000000 as I've defined it in the defs.h tab)
- deviceID = xx (whatever TMCC ID# you've assigned your engine)
- commandField = 00 (as shown on page 5 of the Lionel document for horn command)
- dataField = B11100 (also as shown as page 5 for horn command)
- repeats = 1 (transmit this command 1 time)
so our call is:
sendTMCCCommand(ENGType, xx, B00, B11100, 1); //blow horn
Some other examples:
sendTMCCCommand(ENGType, xx, B11, 10, 1); // set engine speed to step 10
sendTMCCCommand(ENGType, xx, B00, B10101, 1); // numeric 5 for slow dialogue