Extrom Technology

The MS4911 module allows you to encapsulate any message in the
NMEA, arriving via a serial port of type RS485, within a
function 43 of the MODBUS TCPIP protocol made available through an interface
ethernet cable per 10Base-T connector.
IoT CLOUD Connection
In addition to this feature, the module has the ability to provide the same
information through an IoT CLOUD platform and store the same
to provide hisds at any time.
Internal Structure
Internally the module consists of 2 processors, one in charge of
interface the physical Ethernet connection through a Socket normally in the
port 502 and another person in charge of allowing access via Wifi by placing
automatically the NMEA information available in NUVEM IoT and your bank
from data to hists.
Configuration via Web Server
Both processors have access to their built-in WebServer that allows the configuration of their parameters.
In cado only Server via Wifi it is necessary that it is connected to an Acess Pointer to provide your access
via Wifi. In the case of the ethernet cable processor, access to your Server is only possible via a Switch connected to
an Ethernet Network.
Internal message processing
In its internal structure the processor in charge of receiving the NMEA code via an RS485 serial interface is
even in charge of maintaining the connection to our MQTT Cloud Server via a Wifi provided by the
customer. You can use GSM modules with AP/Wifi interface.
This processor in question is tasked with receiving a number of NMEA messages and storing in its
circulating queue for a while.
The second processor in charge of performing Stack MODBUS TCPIP system routines maintains communication
between the two processors and whenever an external request via MODBUS TCPIP in your Socket by the
port 502 is made, it makes an internal request to the other processor and it in turn removes a
message from its internal queue and transmits to this processor that performs a encapsulation of this message in the
modbus protocol of function 43.
This queue of the first processor is dynamically updated by the external device that generates the NMEA messages
delivered to your RS485 serial port.

Access to the MODBUS/TCPIP interface configuration page, through login "admi" and password "ms4911", allows
user to modify more important parameters:
1. Access address of your configuration page: "IP Port", usually port 80
2. Enable switch DHCP server usage: "Abilita DHCP", normally selected
3. NMEA TCPIP Access Socket Access Port: "Socket Port", normally 30
4. Socket address port for MODBUS TCPIP access: "Socket Port", normally 502
5. Device address in MODBUS protocol: "Device MODBUS", usually 1 or 2, etc...
6. Change Login access to this page.
7. Change Password to access this page.

NOTE:
1. Serial port RS485 Half Duplex (2 wires) although bi-directional is always in "input" mode or
NMEA code listening mode.
2. The System processes only NMEA protocol other type of serial data information will be discarded.
3. The MODBUS TCPIP protocol is implemented only for error responses and FUNCTION 43 - READ
DEVICE IDENTIFICATION that in this implementation is used to carry an NMEA 0183 sentence, the
other functions 16, 15, 6, 5, 3, 2 and 1 are not implemented in this application.
4. Any need to activate these functions may be requested in manufactures.
5. NMEA sentences have a limitation of up to 245 characters, if higher will be discarded by the
firmware.
6. Socket Port access connections at address 30 serve to get NMEA sentences directly
ethernet network without the need for the MODBUS protocol, removing from the internal queue of the system this
judgment, but it is concurrent to the other access via MODBUS TCPIP.