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Pro2 Master Module Communications

Pro2 Master Module Communications

The Pr02 Master Module is a flexible SCADA device for controlling valves and remote devices. It works great with with the long-range data radio modem that Raveon supplies to people who use this product. Raveon does not provide it, but it works with our wireless radio modems in remote areas. The Pro2 is designed to control lights, pumps, irrigation valves, beepers, door locks, and many other electrically controlled devices. The 8 output signals switch DC voltage and are reliably protected against Electro-Static Discharge (ESD) and lightning surges.

The controller interface uses Ethernet or RS232 interfaces, so the Pro2 is often used with Raveon’s long-range data radio modems. The advantages of using wireless data radio modems to communicate to the Pro2 are:

  1. Long Range communications. Using Raveon’s wireless modems, you can control Pro2 so over 100s of square miles.
  2. Multiple connections. Raveon radios have 16 bit IDs, so 65000 Pro2 can be communicated to in unique and secure ways.
  3. Secure communications. Raveon’s wireless modems utilize secure AES encryption, so it is secure and reliable to communicate with. If only wires were used, the system would easily be able to be hacked.
  4. Low Cost. Installing and running wires across hundreds of meters is expensive, where wireless connections need very little labor to install. And wireless connections can be moved around every easily unlike wired connections.

What are the features of a Pro2?

  • ON – OFF control of valves, lights, and other devices. No need to run back to a PC to turn a zone on (or off).
  • Each output has a LED to indicate if it is running or idle.
  • All valve wires and connections are protected against lighting surges.
  • RS232 and network connections protected against ESD and lighting.
  • The 8 outputs are protected against overloading by a self-resetting electronic fuse.

Using Data Radio Modems to communicate with SCADA devices like this Pro2 or a Rain8net:

Raveon’s RV-M21 series of data radio modems have RS232 serial interfaces that work with the PC controller and all of the remote controllers in the field.

RAZN Registers

This section describes the Registers stored in the Remote Autonomous Zone Node. Registers can be ready with commands, TOAA, or MODBUS messages.

There area many registers that were stored by the RAZN as it monitors IO terminals and internal features and operations also.

The number in the beginning of the description below is the Register Number.

1-64 GPIO OUTPUT bit status. These are the main GPIO bits on the front of the product Address 1-16 are bits 0-15.

1001 All Output Bits status in this one 16 bit register. This register holds the bit state of output pins 0-15 within this one register.

2200-2215 Up Counter registers for IO 0 – IO 15 bits when in input mode. The Up Count register ticks up every time an input bit state changes from 0 to 1. Write commands can be used to reset the counter.

2300-23015 Up Timer registers for IO0 – IO15 bits times how the bit has been up. The Up Timer register counts the time in mS a bit is on (1)

2400-24015 Down Timer Registers for IO0 – IO15 bits times how long the bit has been down (0). The Down Timer register counts the time a bit is off (0).  Write commands can be used to reset the timer. Time is in milliseconds (mS).

2600-2615 ON Time Counter   It is the number of Seconds an IO pin is ON or was On

5000 Input Voltage to the RAZN device in mV

5002 Device temperature in degrees C. This is the RAZN’s computer board temperature. Very similar to the environment.

5200 Accelerometer, X The G force in X axis of the RAXN device.

5201 Accelerometer, Y The G force in Y axis of the RAXN device.

5202 Accelerometer, Z The G force in Z axis of the RAXN device.

5203 Accelerometer, Motion. The value of the RAZN motion.

6000-6015 Analog input, ADC value. 6000-6015. Register 6000 is input 0, 6001 is input 1

6060-6075 Temperature sensors on the ADS input are computed here.   

6400-6415 Analog input voltage value. 6000-6015. Register 6400 is input 0, 6401 is input 1.

6540-6555 4-20mA 16 bit integer current sensor value. Register 6540 is input 0, 6550 is input IN# 10

21002 Products Serial Number.

56000 Firmware Version information.

GNSS Tracking Technology

Years ago, the GPS (Global Positioning System) was created in America as a constellation of medium earth orbit satellites. Now many other countries can to tracking with the new Global Navigation Satellite Systems (GNSS) technologies.

The frequencies used in various GNSS systems are:

GPS: 1575.42 MHz
Galileo: 1575.42 MHz
QZSS: 1575.42 MHz
BeiDou: 1561.098 MHz

6.25 kHz FM Information

6.25kHz channels were split from 12.5 kHz channels by the FCC. Raveon’s RV-M6 data radio modem can operate on 6.25kHz, 12.5kHz, or 25kHz wide channels.

Now the FCC licenses 6.25 kHz channels on “offset” frequencies within the previous 12.5 kHz channel

6.25 kHz channels are “dropped in” between existing 12.5 kHz radio channels. They allow as close as 6.25 kHz from the center of the 12.5 kHz channel.

The FCC created additional narrow-band spectrum by adding hundreds of new licenses with 6.25kHz bandwidth.

If you have a 12.5 or 25kHz channel, you can create two or four offset 6.25kHz channels. This may require you get a waiver from the FCC.

Modulation with 4-level FSK uses 2 bits per symbol. Typical FM deviation for 6.25kHz 4L channels is:

Bits:00 Deviation: -1050Hz
Bits:01 Deviation: -350Hz
Bits:11 Deviation: +350Hz
Bits:10 Deviation: +1050Hz

FCC Emission Designator

An Emission Designator code is associated with a frequency channel that gives information about the channel’s frequency bandwidth and the nature of the signal on that frequency.

Raveon’s FM Data Radios typically use these Occupied Bandwidths. See data sheets or contact sales team for detailed Occupied Bandwidth information.

Emission Designator RF Bandwidth FM Deviation for Data Comm. Occupied Bandwidth
15K0F1D 25kHz 4.4kHz 15kHz
11K0F1D 12.5kHz 2.2kHz 11kHz
4K0F1D 6.25kHz 1.1kHz 4kHz

If you need a different Occupied Bandwidth, contact Raveon’s sales or support team and we can setup a radio to other power and deviation settings to ensure it meets your bandwidth requirements.

What is an FCC Emission Designator?

For a wireless device, am Emissions Designators are a 6 to 8 character code identifying the electromagnetic modulation characteristics. Codes represent different features of wireless emissions from different products.

Emission Designators are used by governments including the FCC and ACMA.

Current Modern Emission Designators

Emission Designator consists of 7 characters as described here:

The first four characters identify the bandwidth required to transmit data at the rate with the required system performance that is used.

The fifth character is the type of modulation of the main carrier.

The sixth character is the signal modulating the RF carrier.

The seventh character is the type of information transmitted.

Modulating signal codes

The 6th character of the emission designator specifies the type of data that is being transmitted. Here is a list of transmission types:

  • N – None Transmission. (RX only).
  • A – Aural Morse Code telegraphy for people.
  • B – Telegraphy for machines, RTTY, fast Morse Code.
  • C – Analog fax.
  • D – Data, telemetry, telecommand.
  • E – Telephony, voice, broadcasting sound.
  • F – Video, television.
  • W – Combinations of the above
  • X – All cases above not covered.

Modulation Type Codes

N   None
A   AM (Amplitude Modulation), double sideband, full carrier
H   AM, single sideband, full carrier
R   AM, single sideband, reduced or controlled carrier
J   AM, single sideband, suppressed carrier
B   AM, independent sidebands
C   AM, vestigial sideband  (commonly analog TV)
F   Angle-modulated, straight FM
G   Angle-modulated, phase modulation (common; sounds like FM)
D   Carrier is amplitude and angle modulated
P   Pulse, no modulation
K   Pulse, amplitude modulation (PAM, PSM)
L   Pulse, width modulation (PWM)
M   Pulse, phase or position modulation (PPM)
Q   Pulse, carrier also angle-modulated during pulse
W   Pulse, two or more modes used

Here is an example of an Emission Designator, that shows and explains the different items to indicate in the Emission Designator.

Emission Designator structure and Emission Designator Example for 11K0F1D 

Emission Designator structure and Emission Designator Example for 11K0F1D 

1 2 3 4 5 6 7
Necessary Bandwidth Emission Classification Symbol Necessary Bandwidth decimal        
11.0 K  (Kilohertz) .0 FM Digital, on-off or quantized, no modulation. Data transmission, telemetry, telecommand;  
11 K 0 F 1 D  

Calculating Emission Designation Bandwidth (BW)

The math for calculating bandwidth of an FM signal can be simple algebra.

BW = 2 x { Baud Rate + FM Peak deviation }

Baud Rate is: modulation frequency, is the highest frequency of the data rate you send out over the air. For voice communications, modulation frequency is generally accepted to be 3000 Hz. In a radio system with the peak deviation of 2.5 kHz, the Audio formula works out like this:

BW= 2 (3000 + 2500 ) = 11 kHz

For data communications, the formula is: Bandwidth = B + (K × Shift)
Where BW = (speed of transmission in baud) + (K × Frequency shift in hertz) In FSK mode the value of K is = 1.2. For example:

The bandwidth of a 3300-Hz shift, 9600 baud ASCII signal transmitted as a F1D emission on a wide-band channel :
BW = 9600 + (1.2 × 3300) = 13,560 Hz
At 4800 deviation, BW = 15kHz on wideband.

On a Narrow band channel, 4800 baud, 2.2kHz deviation
BW=4800+(1.2*2200) = 7440Hz

For FM modulation (FSK) data transmissions, the bandwidth formula can be: BW = Baud + 2 * FMdeviation * 1.2

The FCC shows Binary Frequency Shift Keying math:
Bn = 3.86D + 0.27R D=deviation R=data rate
4800baud at 2.3kHz deviation = 10.2kHz bandwidth.

DD1494 Data Radios

The DD1494 form is submitted in stages that coincide with the phases of the DoD acquisition process.

RF performance and RF spectrum information are put into the DD form 1494 so the government can allocate frequencies for a radio.

Raveon’s Data Radio modems are used on many different frequencies that were setup using DD1494 forms. Raveon will work with you to make and submit the form, and we can create the Form for you and get it to you.

J-12: The J-12 process is created to handle and protect the proprietary data. Proprietary data will not be abstracted, or entered into reports, or into data bases. The JF-12 process usually takes six to twenty-four months to complete.

JF-12 are processes for Coordination of Electromagnetic Frequency Spectrum with Host Nations

The J-12 Certification Process:
The purpose ofJ-12 certification is to ensure that the operational frequency band and type of service are in conformance with respective national and international tables of spectrum allocation; that the equipment conforms to applicable statutes, regulations, directives, standards, and specifications; and that the equipment can operate in its intended environment without causing harmful interference to other equipment operating in the same environment. Common services for radios are: microwave, radar, radio, satellite, wireless, …
The entire JF-12 process usually requires between six to twenty-four months to complete.

DD Form 1494

The main goal of the DoD’s spectrum management program is to develop and efficiently manage the DoD’s use of spectrum during the frequency allocation. Achieving the goals minimizes the potential for interference during the fielding and utilizing of spectrum dependent equipment and is critical due to significant increases in the use of the available electromagnetic spectrum due to technological advancements and spectrum being reallocated away from military use, or being opened to sharing with commercial use.

DoD acquisition policy states that the funds for the acquisition, research, development, production, purchase, lease, or use of weapon systems, information management systems, electronic warfare (EW) systems, or other systems that require use of the electromagnetic spectrum will not be released by the obligating authority until an application for frequency allocation has been approved.

In the Federal level, the Defense Department and the NTIA are actively involved in DD1494 certification process also known as J-12 process.
Here is an overview of the Phases in the process.

For DOD use, complete a DD1494 form and use the J-12 or JF-12 spectrum-certification process.

The procedures the DoD developed for establishing host­-nation agreements for spectrum is the JF-12 process.

Definitions of Terms in DD1494 forms and documents

Army Interference Resolution Program (AIRP)
C o m m u n i c a t i o n s E l e c t r o n i c s Services Office (CESO)
Combined Communications Electronics Board (CCEB)
Cost and Operational Equipment Analysis (COEA)
Department of the Army (DA)
Defense Communications System (DCS)
Deputy Chief of Staff for Information Management (DCSIM)
Director of Information Management (DOIM)
Government Master File (GMF)
Office of the Secretary of the Army (OSA)
Joint Spectrum Interference Resolution (JSIR)
Joint Spectrum Center (JSC)
Joint Readiness Training Center (JRTC)
Major Subordinate Command (MSC)
US Army Signal Operation Instructions (SOI)
Spectrum Planning Subcommittee (SPS)
Test and Integration Working Groups (TIWGs)
T r a i n i n g a n d D o c t r i n e Command (TRADOC)
United States Army, Pacific (USARPAC)
Assistant Secretary of the Army for Research, Development and Acquisition (ASA (RD&A))

Fast Long Range Radio

This is information about a communication time test with an oscilloscope to measure and show how fast our long-range LoRa technology works.

Below is a picture of the data communication time.

The Green pulses were inbound 16 bytes of data on a UART into Radio #1 at 38400bps.

The Yellow pulses are the outbound 16 bytes of data on a UART in Radio #2 that received the over-the-air message from #1.

So from the time the first message was sent into the radio it fully came out of the other radio in 40mS. 

This is Raveon’s RV-M50 ISM band transceiver that uses LoRa technology.

This message passed along over the M50 radio modes was doen with them in the spreading factor of 7. With LoRa technology, there are many spreading factor options to utilize. Following is a list of over-the-air data rates for LoRa data radio modems.

In Raveon Radios, Channel data rate varies by spreading factor, spreading factor can be set with ATSF <val>, where <val> is set according to the table below:  

ATSF Setting Bit Rate for 500kHz Channels Duration for 20 Data Bytes Dur. 100 Bytes
Typical Packet FEC=0(4/4) FEC=1(4/5) FEC=4(4/8) FEC=1(4/5)
7 21.87 kbps 20mS 25mS 30mS 52mS
8 12.50 kbps 44mS 44mS 56mS 92mS
9 7.03 kbps 64mS 78mS 100mS 160mS
10 3.90 kbps 125mS 144mS 184mS 310mS
11 2.14 kbps 240mS 265mS 340mS 580mS
12 1.17 kbps 480mS 520mS 680mS
(Don’t Use)
1020mS (do not use)

For packets greater than 10-20 bytes, we recommend not to use Forward Error Correction FEC 4(4/8) with the Spreading Factor ATSF of 12, because packets are too long for the system. 

The fast efficient over-the-air protocol is ideal for sending data between RTUs and between Master Controllers and RTUs. This RV-M50 radio modem can send information between two devices 20-50 times per second, and even get responses back in 40mS, so a round-trip inquiry can take place in 80mS out and back.

Using RF Modem ID Codes

Raveon has products with various radio identification ID features.  Each radio has an ID, and is assigned and ID to talk to.  This Application Note AN240 describes how ID processing works and describes all the ID features Raveon’s radios have that use the IDs such as broadcasting and repeating. 

Addressing Basics

One of the more powerful aspects of Raveon’s Radio Modems are its addressing scheme.  Addressing allows multiple radio systems on the same frequency to co-exist, and not interfere with each other.   Addressing is used to differentiate one radio modem from another.  Each unit has a unique number, so that when data or a GPS position report is received, the radio modem  that sent the message is known.  Use the Data Encryption Security KEY to protect messages from being intercepted.  Use the ID addressing to identify individual radio modems and GPS transponders.

This addressing scheme allows up to 65,000 (FFFF) radio modems to be on one radio channel, or split-up into sub-groups. A way to disable addressing altogether is set the Address Mask to 0000 (ATMK 0000 command).
For More Technical information about how to utilize Radio ID codes, read Application Note AN240.

You can also setup radios in Groups by using the Address Mask as F000, FF00, or FFF0 depending upon the group size you would like. F000 masks of the three lower ID numbers, so only the first number in the ID needs to match.

One effect of this is that an address mask of 0000 will cause the Radio Modem modem to received any data from any unit that transmits.  The Destination Address will effectively be ignored and all data received if the mask is set to 0000.

Listen Address:

The Listen Address is a second ID programmed into the radio, that the unit will Listen for.  The Listen Address is configured using the ATLA xxxx command.  If the Listen Address is set to FFFF, then this feature is ignored, and FFFF is the factory default so by default the Data Radio Modem does not use the Listen Address.

Store-and-Forward Repeating

The RADIO MODEM modem has a built-in wireless repeater.  Each RADIO MODEM is capable of not only sending and receiving data from/to its serial port, but also re-transmitting data packets it receives over-the-air data. 

Automatic Repeater Configuration

The easiest way to enable store-and-forward repeating is the use the REPEAT 1 command. REPEAT 1 will turn on the store-and-forward feature, and configure it to repeat all packets the radio can hear on the air.  REPEAT 0 disables store-and-forward repeating.

It is highly recommended that you use this method to configure your RADIO MODEM as a repeater.

Important:  The Unit ID of the repeater must be unique in the system. No other radio modem in the system can have the ID of the repeater.

Serial Data Communications

Electronic communications is all about interlinking circuits (processors or other integrated circuits) to create a symbiotic system. For those individual circuits to swap information, they must share a common standard communication protocol. Many communication protocols have been designed to achieve data exchange.

The most common serial communication protocols are RS232, RS485, RS422, USB, and Ethernet.  But because USB and Ethernet require powerful interfaces with complex protocols, many efficient devices utilized RS232, RS485, and RS422 which is what this note is all about.

AN236(SerialComm) (pdf) Serial data communications application note.  The advantages of using RS422, the advantages of RS485, and the advantages of RS232 serial data communications. What’s the difference between RS232 and RS-485? The answer is here.

Serial Communications RS232, RS485, RS422

AN236 Summary

AN236(SerialComm) Application Note PDF

Electronic communications is all about interlinking circuits (processors or other integrated circuits) to create a symbiotic system. For those individual circuits to swap information, they must share a common standard communication protocol. Many communication protocols have been designed to achieve data exchange.

The most common serial communication protocols are RS232, RS485, RS422, USB, and Ethernet.  But because USB and Ethernet require powerful interfaces with complex protocols, many efficient devices utilized RS232, RS485, and RS422 which is what this note is all about.

Protocol Comparison Chart

RS-232 RS-422 RS-485
Cable Single ended Single ended multi-drop Multi-drop
Number of Devices 1 transmitter
1 receiver
1 transmitter
10 receivers
32 transmitters
32 receivers
Communication Mode Full duplex Full duplex,
Half duplex
Full duplex,
Half duplex
Maximum Distance 50 feet at 19.2 kbps 4000 feet at 100 kbps 4000 feet at 100 kbps
Max Data Rate (50 feet) 1 mbps 10 mbps 10 mbps

Serial Protocols

The RS232, RS485, RS422 serial protocols only relate to the hardware interface, not the software protocols used to make the devices communicate. There are many protocols that exist in the market place so one cannot assume interoperability between different manufacturers of “RS232” ports.

To define Instruments that supports a mixture of industry standard and proprietary serial protocols:

Modbus RTU

This protocol is used in industrial applications and most SCADA PLC’s have drivers for Modbus RTU. The Modbus protocol is well published and every manufacturer can and does determine its own addressing scheme. The manufacturer must supply the addressing scheme, register type, and Modbus commands that is supports.

ASCII protocol

ASCII is popular because it is easier than Modbus to write your own driver in a PLC or a PC. Most every manufacturer’s protocols are not usually compatible.

The Advantages of RS485 and RS422 vs RS232

RS485 and RS422 use differentiation. Two wires are required for each signal.  The figure below shows a single RS485 / RS422 signal being transmitted. To transmit a logic 1, line B is high and line A is low. To transmit a logic 0, line B is low and line A is high. The advantage of this arrangement is that signals can be transmitted faster and over greater distances than is possible with a single wire.

The main difference between RS422 and RS485 is the types of communications allowed. RS422 allows only one-way (simplex) communications between one driver, and as many as ten receiving devices. To control devices and need no feedback from them, RS-422 multidrop network will work well. RS485 was designed to address the multi-drop limitation of RS422, allowing up to 32 devices to communicate.


An RS232 serial bus consists of just two communication wires – one for sending data and another for receiving. As such, serial devices should have two serial pins: the receiver, RX, and the transmitter, TX.  Because the communication data is based upon the voltage on the wires, relative to the ground level, a ground connection must be made between devices that communicate with RS-232.  Here is an RS232 wiring diagram:

A digital 1 voltage is:  -3V to -25V

A digital 0 voltage is:  +3V to +25V

RS232 data is sent serially, each bit is sent one after the next because there is only one data line in each direction. This mode of data transmission also requires that the receiver knows when the actual data bits are arriving so that it can synchronize itself to the incoming data. To achieve this a logic 0 is sent as a synchronization start bit.


RS422 is designed to be tolerant of noise and forgiving of long cable runs. It achieves this by using a differential current drive output which has high immunity to noise. The noise immunity enables RS485 systems to operate over very long connections, much better than RS232, US, and Ethernet.

Each signal uses two wires to pass the data. The differential voltage on the A and B wires represent the digital value. If B>A the value is 1. If A>B then value is 0.

Input Signal   A    B Output Signal
0   1     0 0
1   0     1 1

RS422A Standard Specifications

  • 1 Driver, up to 10 Receivers

Line Length for Max Data Rate:

  • 40 Feet = 12m 10 Mbits/sec
  • 400 Feet = 122m 1 Mbits/sec
  • 4000 Feet = 1219m 100 kbits/sec

A multi-drop wiring has many desirable advantages, RS422 devices cannot be used to construct a truly multi-point network. A true multi-point network consists of multiple drivers and receivers connected on a single bus, where any node can transmit or receive data.  RS422 networks are often used in a half-duplex mode,


RS485 is still popular. It is similar to the RS422 upon which it is based. The RS485 port has been used for many years.  RS485 has many advantages over both RS232 and USB when it comes to applications in noisy industrial environments. RS422 devices can be used on an RS485 bus network if they are only used as recipients.

The main difference between RS422 and RS485 is that up to 32 transmitter receiver pairs may be present on the line at one time on RS485. A 120 Ohm resistor must be used to terminate the main line.

RS485A Standard

  • Up to 32 Driver/Receiver Pairs

Line Length Max Data Rate

  • 40 Feet = 12m 10 Mbits/sec
  • 400 Feet = 122m 1 Mbits/sec
  • 4000 Feet = 1219m 100 kbits/sec

When instruments are described as having an RS485 interface this tells you nothing for sure about the signals being transmitted. Usually though only the Transmit Data (TX) and Receive Data (RX) of a normal serial port are converted to RS485 or RS422. The other signals of the serial port are not used. Three arrangements are commonplace: Write only, 4-wire (full duplex) and 2-wire (half duplex).  The  “2-wire” RS-485 connection is shown below.

RS485 half-duplex can use just two wires to communicate with up to 32 device, one at a time.  Each device has the ability to turn off its output drivers, so only the one device that is linking to the host outputs a signal on its TX lines.

Termination Resistors

Termination resistors should be placed on both ends of the twisted pair of wires. The impedance value should be the same value of the characteristic impedance of the twisted pair and should be placed at the far ends of the cable.

For cables that are 2000 feet or less, a termination resistor is not needed at baud rates of 9600bps or less.

If a termination resister is required, a 120? or greater should be used.  No more than 2 termination resistors should be used, one at each end of the RS485 transmission line.

For additional information, contact:

Raveon Technologies Corporation

2320 Cousteau Court

Vista, CA 92081 – USA

Phone: 1-760-444-5995
Fax: 1-760-444-5997