NAME

       modbus_rtu_set_custom_rts - set a function to be used for custom RTS implementation

SYNOPSIS

       int modbus_rtu_set_custom_rts(modbus_t *ctx, void (set_rts) (modbus_t ctx, int on))

DESCRIPTION

       The modbus_rtu_set_custom_rts() function shall set a custom function to be called when the
       RTS pin is to be set before and after a transmission. By default this is set to an
       internal function that toggles the RTS pin using an ioctl call.

       Note that this function adheres to the RTS mode, the values MODBUS_RTU_RTS_UP or
       MODBUS_RTU_RTS_DOWN must be used for the function to be called.

       This function can only be used with a context using a RTU backend.

RETURN VALUE

       The modbus_rtu_set_custom_rts() function shall return 0 if successful. Otherwise it shall
       return -1 and set errno to one of the values defined below.

ERRORS

       EINVAL
           The libmodbus backend is not RTU.

AUTHORS

       Jimmy Bergström <jimmy@ekontroll.com>

       The libmodbus documentation was written by Stéphane Raimbault
       <stephane.raimbault@gmail.com>