Icom 746 pro will not enter USB data mode, if entered manually it will revert to RTTY.
Examination of ini file
CmdType=HEX
PTTOn=FEFE66E01C0001FD
PTTOff=FEFE66E01C0000FD
ModeUSB=FEFE66E00601FD (Sets radio to USB mode)
ModeUSB_D=FEFE66E00604FD (sets radio to RTTY mode)
ModeFM=FEFE66E00605FD
SetFreq_Data_method=BCD
SetFreqVfoA_Cmd=FEFE66E005{}FD
SetFreqVfoA_param_length=10
SetFreqVfoA_hz_res=1
ReadFreqVfoA_Cmd=FEFE66E003FD
ReadFreqVfoA_Result_Data_method=BCD
ReadFreqVfoA_Result_hz_res=1
ReadFreqVfoA_Result_Length=22
ReadFreqVfoA_Result_Freq_Start_Pos=11
ReadFreqVfoA_Result_Freq_Length=10
Upon examination of Icom 746pro manual I cannot find a setting to change to usb to Data mode
so now I am stumped
I downloaded the 746Pro manual and there is indeed CAT command for Data modes. You need 2 commands, the first to set to USB mode (not RTTY) and the second to turn on the Data Mode. Try this string. I dont have an 746 so will have to rely on a 746 owner to test.
ModeUSB_D=FEFE66E00601FD,FEFE66E01A0601FD