Lantronix XPort APS: Modbus Protocol User Guide - Page 21

5: WiPort and WiBox Implementation The Modbus master/slave functionality on the WiPort and WiBox is similar to the Modbus implementation on other platforms such as the UDS1100 or XPress-DR. The difference is the configurable pins on the WiPort (CP0-CP10) and the WiFi settings on the WiPort and WiBox are configurable from the Setup Menu. The WiPort and WiBox have 2 serial ports. Choose the serial port the firmware uses for sending and receiving Modbus/RTU or Modbus/ASCII serial data under the Serial & Mode Settings menu option. Note: Channel 1 on WiBox only supports RS-232 while Channel 2 supports RS-232 and RS-422/RS-485 2/4-wire modes. Use serial connector (1=CH1 2=CH2) (1) ? The menu option for Modem Control Settings is replaced with Modem/Configurable Pin Settings on the WiPort. The options are: CP0 Function (hit space to toggle) GPIO (In) CP0 Function (hit space to toggle) GPIO (Out) CP0 Function (hit space to toggle) DTR (Out) CP0 Function (hit space to toggle) Diag LED CP0 Function (hit space to toggle) Status LED-G CP0 Function (hit space to toggle) Status LED-Y CP0 Function (hit space to toggle) RS485 Select CP0 Function (hit space to toggle) RS485 2-Wire CP0 Function (hit space to toggle) RS485 4-Wire CP0 Function (hit space to toggle) Defaults(In) The assignment for each configurable pin is set by cycling through the menu options by entering a space or any key other than Enter.  GPIO assigns the pin as a general purpose input or output. The GPIOs can be written and read via Modbus/TCP when in slave attached mode.  DTR is the Modem Control Output (MCO) signal for Data Terminal Ready.  Diag LED, Status LED-G and Status LED-Y are the outputs for diagnostic LED (red), green status LED, and the yellow status LED.  RS485 Select is an output made active when configuring the serial channel for RS422/485 operation.  RS485 2-Wire and 4-Wire are outputs made active when configuring RS422/485 2-Wire or 4Wire operation respectively.  Defaults is an input read at startup that tells the firmware to reset configuration to factory defaults. After assigning the applicable function by pressing Enter, you are then asked if the pin is inverted (active low). CP0 Function (hit space to toggle) GPIO (In) Invert (active low) (Y) ? A function should be assigned to each configurable pin. GPIO (Input) should be the default for all unused or unassigned pins. Modbus Protocol User Guide 21