With the GMI command, you can ask the board to send meta information. After receiving the command, the board will send all meta information in separate messages per datatype. First in the string the identifier of the message, then the type of data, the number of tagnames (0..99) and then the individual tagnames and there pin numbers, separated by commas. 

CommandHMIBoardSyntaxRemark
GMISendReceive@GMI 
GMIReceiveSend@GMIDI,<#>,<tagname,pin,report,poll,mask>,<..>
@GMIDO,<#>,<tagname,pin,report,poll,auto>,<..>
@GMIAI,<#>,<tagname,pin,poll,mask>,<…
@GMIAO,<#>,<tagname,pin,poll,auto>,<…
@GMISO,<#>,<tagname,pin,poll,auto>,<..
@GMIDM,<#>,
tagname,trigger,echo,poll,mask>,<..
@GMITT,<#>,<tagname,pin,poll,mask>,<…
@GMIBM,<MANUAL|AUTOMATIC>
@GMIMS,<MASK|AUTOMATIC>
Digital InDigital OutAnalogue InAnalogue Out (PWM)Servo OutDistance Measurement In (HC-SR04)Temperature sensor (DS18B20)Board modeFiled Masking mode
Possible error messages coming from the board
%GMI-UNKCMD-BTSERIAL, String not processed