M4 Wireless Data Transceiver
“
Product Information
Specifications
- Working Voltage: 3.3 – 3.6 V
- Working Temperature: -40°C to +85°C
- Working Humidity: 10% to 90% RH
- Storage Temperature: -45°C to +85°C
- Electrostatic Discharge Voltage (Contact
Discharge): 4 KV - Electrostatic Discharge Voltage (Air
Discharge): 6 KV
Product Usage Instructions
1. Overview
The M4 is a built-in transceiver LORA radio station designed for
the lawn mower market and IoT wireless transmission applications.
It supports the 868MHz and 915MHz ISM unlicensed frequency bands,
complies with radio regulations in Europe and the United States,
and offers features like frequency hopping anti-interference, relay
networking, and OTA firmware upgrades.
2. Product Features
- Supports ISM unlicensed bands in Europe and America: 863-870
MHz and 902-928 MHz - LBT+AFA compliance for local radio regulations in Europe and
the United States - Supports point-to-point and point-to-multi communication
- Integrated transceiver for differential data transmission and
two-way communication - Fast frequency hopping and strong anti-interference
ability - Supports relay networking for smooth communication between
yards - Supports radio frequency power control in ISM bands of Europe
and the United States - Open upgrade protocol for OTA firmware upgrades
- IC, CE, FCC certifications supported
3. Technical Parameters
3.1 Working Conditions
- Working Voltage: 3.3 – 3.6 V
- Working Temperature: -40°C to +85°C
- Working Humidity: 10% to 90% RH
- Storage Temperature: -45°C to +85°C
- Electrostatic Discharge Voltage (Contact
Discharge): 4 KV - Electrostatic Discharge Voltage (Air
Discharge): 6 KV
3.2 Power Consumption Parameters
- Emission Power: 100mW
- Current for Emission (at 100mW): 135 mA
- Current for Emission (at 25mW): 85 mA
- Receive Current: 20 mA
3.3 Radio Frequency Characteristics
Note: Requires a 3.3V power supply.
- Work Frequency: 902.5-927.49 MHz
- Working Mode: Half-duplex
- Channel Bandwidth: 250 kHz
- Modulation Method: CSS
- Carrier Power: 100mW
- Power Consumption (Typical Values):
- – High power to transmit: 445mW @3.3V DC (output 100mW
power) - – Transmit low power: 280mW @3.3V DC (output 25mW)
- – Whole standby: 66mW @3.3V DC
- – High power to transmit: 445mW @3.3V DC (output 100mW
- Receiving Sensitivity: Superior to -118dBm
@BER 10^-5,11000bps - Co-channel Suppression: >-12dB
3.4 Modem
- Air Speed: 11,000 BPS, 62,500 BPS
- Serial Port Rate: 9600bps, 19200bps, 38400bps,
115200bps
3.5 Operating Temperature
- Working Temperature: -40°C to +85°C
- Storage Temperature: -45°C to +85°C
3.6 Communication Interface
The serial port uses standard TTL level.
Frequently Asked Questions (FAQ)
Q: What certification standards does the M4 product comply
with?
A: The M4 product is compliant with IC, CE, and FCC
certifications.
Q: What are the supported frequency bands for the M4
product?
A: The M4 product supports the ISM unlicensed bands in Europe
and America: 863-870 MHz and 902-928 MHz.
Q: Can the M4 product support OTA firmware upgrades?
A: Yes, the M4 product supports OTA upgrades of radio
firmware.
Q: What is the working voltage range of the M4 product?
A: The working voltage range of the M4 product is between 3.3V
and 3.6V.
Q: What is the communication interface of the M4 product?
A: The communication interface of the M4 product uses a serial
port with standard TTL level.
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M4 Data Transmission Product Specification Sheet
File number: Product model: Product name: Release time:
NQR.CP-M4-2409-019
M4 Built-in data transmission and
reception radio
2025.03.12
Seria l Numbe r
Modify sections/claus
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All
Notes on Document Revisions
Revise the summary
Version Modificati number on date
Modifiers
Approver
Build the first draft
V1.0 2024.9.2
Chapters 2 and Update power parameters and
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V1.1 2025.3.12
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refine pin descriptions
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4
Catalogue
I. OVERVIEW ………………………………………………………………………………………………………. 1 1.1 Product Features……………………………………………………………………………………………….. 1 1.2 Application Fields ……………………………………………………………………………………………… 2 2 . TECHNICAL PARAMETERS ……………………………………………………………………………… 2 2.1 Working Conditions………………………………………………………………………………………….. 2 2.2 Power consumption parameters ……………………………………………………………………… 2 2.3 Radio Frequency characteristics ………………………………………………………………………. 3 2.4 Modem………………………………………………………………………………………………………………. 3 2.5 Operating Temperature ……………………………………………………………………………………. 3 2.6 Communication Interface ………………………………………………………………………………… 3 2.7 Structural Characteristics………………………………………………………………………………….. 4 3 . PIN DEFINITIONS ……………………………………………………………………………………………. 4 4 . EXTERNAL REFERENCE HARDWARE DESIGN ………………………………………………. 6 4.1 Recommended wiring diagram ……………………………………………………………………….. 6 4.2 Module Dimensions………………………………………………………………………………………….. 8 4.3 Passing process requirements …………………………………………………………………………. 8
1
Overview
M4 is a built-in transceiver LORA radio station developed specifically for the lawn mover market and iot wireless transmission applications. The product supports the 868MHz and 915MHz ISM unlicensed frequency bands and features compliance with radio usage regulations in Europe and the United States, frequency hopping anti-interference, longdistance two-way communication, relay networking, OTA radio firmware upgrade, etc. It meets the demand for wireless communication in the lawn mower market.
Figure 1-1 Appearance of the M4
1.1 Product features
Supports ISM unlicensed bands in Europe and America: 863-870 MHZ and 902-928 MHZ
Supports LBT+AFA to meet the requirements of local radio usage regulations in Europe and the United States
Support point-to-point and point-to-multi communication Integrated transceiver, meeting the requirements of differential data transmission and
two-way communication between sleep and wake-up of base stations Fast frequency hopping and strong anti-interference ability Support relay networking, smooth communication between front and back yards It meets the requirements for radio frequency power control in the ISM band of Europe
2
and the United States, supporting 25mW in Europe and up to 100mW in the Americas Open upgrade protocol, support OTA upgrade of radio firmware IC, CE, FCC certifications are supported
1.2 Application areas
Smart lawn mowers, Internet of Things wireless communication
Technical parameters
2.1 Working conditions
Minimum Typical
Parameters
Maximum Units
value values
Working
3.3
3.3
voltage
3.6
V
Working
-40
–
+85
temperature
Working
10
–
90
%RH
humidity
Storage
-45
–
+85
temperature
Electrostatic
discharge
voltage
–
–
4
KV
(Contact
discharge)
Electrostatic
discharge
voltage
–
–
6
KV
(Air
discharge)
2.2 Power consumption parameters
3
Instructions
Output Parameters
power
Emission 100mW
current
25mW
Receive –
current
Typical values
135 85
20
Unit
mA mA mA
2.3 Radio frequency characteristics
Notes
3.3V power supply
Project
Work frequency Working Mode Channel bandwidth Modulation method
Carrier power
Power consumption (typical values)
Receiving sensitivity Co-channel suppression
Content
902.5-927.49 MHZ Half-duplex 250kHz CSS 100mW High power to transmit: 445mW@3.3V DC (output 100mW power) Transmit low power: 280mW@3.3V DC (output 25mW) Whole standby: 66mW@3.3V DC Superior to -118dBm@BER 10-5,11000bps
>-12dB
2.4 Modem
Air speed Serial port rate
11,000 BPS, 62,500 BPS 9600bps, 19200bps, 38400bps, 115200bps
2.5 Operating temperature
Working temperature Storage temperature
– 40 ~ + 85 – 45 ~ + 85
2.6 Communication interface
Project
Serial port
Standard TTL level
Content
4
Data bits: 8 bits Stop bit: 1 bit Verification: No verification
2.7 Structural characteristics
Project
Size Weight Antenna interface Antenna interface impedance Data interface
Content
25(length)×21(width)×3.7(height)mm About 3g IPEX, stamp hole
50
30Pin SMT
Pin definitions
The M4 pin distribution is shown below:
Pin number
1 2 3
4
Pin Pin name
direction
Pin Uses
GND SWDIO SWCLK
CONFIG
Ground
Input/Output Dangling (for internal use)
Input
Suspended (for internal use)
Input
Low level enters configuration mode, high level data transmission mode; The internal hardware has a pullup 10K resistor to 3V;
5
5
1PPS
Input
Board card 1PPS input
Serial port 1 TX terminal, TTL serial port output,
connected to the external RXD input pin;
6
TXD1
Output
The internal hardware has a pull-up 10K resistor to
3V;
Serial port 1 RX terminal, TTL serial port input,
7
RXD1
Inputs
connected to the external TXD output pin
8
GND
Ground
9
GND
Ground
10
IO3
Input/Output Function extended IO port
11
IO4
Input/Output Function extended IO port
12
RSV
Suspended in the air
13
GND
Ground
14
ANT
Input/Output Antenna interface
15
GND
Ground
16
GND
Ground
Serial 2 TX terminal, TTL serial output, connected to
the external RXD input pin;
17
TXD2
Output
The internal hardware has a pull-up 10K resistor to
3V;
Serial port 2 RX terminal, TTL serial port input,
18
RXD2
Inputs
connected to the external TXD output pin
19
REST
Input
Radio reset (low level works)
Serial port 1 RXD1 buffer is empty status indicator,
high level indicates not empty, low level indicates
20
IO1
Output
empty. The size of each serial port transmission data
packet should not exceed 1000 bytes.
21
IO2
Input/Output Function extended IO port
22
GND
Ground
23
GND
Ground
24
LED TX
Output
Launch status indicator light (High level effective)
25
LED RX
Output
Receive status indicator light (High level effective)
6
26
GND
Ground
27
VCC
Input
Power DC 3.3-3.6V
28
VCC
Input
Power DC 3.3-3.6V
29
GND
Ground
30
GND
Ground
7
4.2 Module size
Views and dimensions are shown below.
Note: There is 6.7*4.9mm exposed copper at the bottom of the radio station for heat dissipation of the internal PA, and this area needs to be soldered onto the PCBA when mounting.
8
FCC Statement This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: – Reorient or relocate the receiving antenna. – Increase the separation between the equipment and receiver. – Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. – Consult the dealer or an experienced radio/TV technician for help. To assure continued compliance, any changes or modifications not expressly approved by the party. Responsible for compliance could void the user’s authority to operate this equipment. (Example- use only shielded interface cables when connecting to computer or peripheral devices). Any Changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.
This equipment complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) This device must accept any interference received, including interference that may cause undesired operation.
Radiation Exposure Statement: The equipment complies with FCC Radiation exposure limits set forth for uncontrolled environment. This equipment should be installed and operated with minimum distance 20cm between the radiator and your body.
The modular can be installed or integrated in mobile or fix devices only. This modular cannot be installed in any portable device, for example, USB dongle like transmitters is forbidden.
This modular complies with FCC RF radiation exposure limits set forth for an uncontrolled environment. This transmitter must not be co-located or operating in conjunction with any other antenna or transmitter. This modular must be installed and operated with a minimum distance of 20 cm between the radiator and user body.
If the FCC identification number is not visible when the module is installed inside another device, then the outside of the device into which the module is installed must also display a label referring to the enclosed module. This exterior label can use wording such as the following: “Contains Transmitter Module FCC ID: 2BM2K-M4 Or Contains FCC ID: 2BM2K-M4”
ISED Statement This device contains licence-exempt transmitter(s) that comply with Innovation, Science and Economic Development Canada’s licence-exempt RSS(s). Operation is subject to the following two conditions:
(1) This device may not cause interference. (2) This device must accept any interference, including interference that may cause undesired operation of the device.
Radiation exposure statement: The device complies with the RSS radiation exposure limits set for uncontrolled environments. The device must be installed and used with a minimum distance of 20cm between the radiator and the body
Le present appareil est conforme aux CNR ISED applicables aux appareils radio exempts de licence. L’exploitation est autorisee aux deux conditions suivantes:
(1) l’appareil ne doit pas produire de brouillage, et (2) Iutilisateur de l’appareil doit accepter tout brouillage radioelectrique subi, meme si le broullage est susceptible d’en compromettre le fonctionnement. Déclaration d’exposition aux rayonnements: L’équipement est conforme aux limites d’exposition au rayonnement RSS établies pour les environnements non contrôlés. Cet équipement doit être installé et utilisé avec une distance minimale de 20cm entre le radiateur et votre corps
RSS-Gen clause 4.3 statement:
If the IC Certification Number is not visible when the module is installed inside another device, then the outside of the device into which the module is installed must also display a label referring to the enclosed module. In that case, the final end product must be
labeled in a visible area with the following:
“Contains IC: 33426-M4″
Requirement per KDB996369 D03
2.2 List of applicable FCC rules
CFR 47 FCC PART 15 SUBPART C has been investigated. It is applicable to the modular transmitter.
2.3 Summarize the specific operational use conditions
This module is stand-alone modular. If the end product will involve the Multiple simultaneously transmitting condition or different operational conditions for a stand-alone modular transmitter in a host, host manufacturer have to consult with module manufacturer for the installation method in end system. This radio transmitter 2BM2K-M4 have been approved by Federal Communications Commission to operate with the antenna types listed below, with the maximum permissible gain indicated. Antenna types not included in this list that have a gain greater than the maximum gain indicated for any type listed are strictly prohibited for use with this device. The concrete contents to check are the following three points. ) Must use an antenna such as Dipole Antenna with a gain not exceeding 1.34 dBi ) Should be installed so that the end user cannot modify the antenna; Fine-tuning of return loss etc. can be performed using a matching network. The antenna shall not be accessible for modification or change by the end user. A modification to the antenna is required FCC/ISED Class II permissive change. This device has been approved as mobile device in accordance with FCC and ISED Canada RF exposure requirements. This means that a restricted minimum separation distance of 20cm between the antenna and any person. A change in use that involves a separation distance 20cm (Portable usage) between the Module’s antenna and any persons is a change in the RF exposure of the module and, hence, is subject to a FCC Class 2 Permissive Change and a ISED Canada Class 4 Permissive Change policy in accordance with FCC KDB 996396 D01 and ISED Canada RSP-100.
2.4 Limited module procedures
The module is a single module, not applicable.
2.5 Trace antenna designs
The module has no tracking antenna be used, not applicable.
2.6 RF exposure considerations
This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with minimum distance 20cm between the radiator & your body. The host product shall show the same or similar statement to the end users in the endproduct manuals.
If the module is installed to a host / end product with a used distance <20cm, additional SAR evaluation or measurement must be followed according to FCC KDB 447498 and RSS102. If the module is installed to a host / end product with multiple transmitters, additional RF exposure evaluation must be performed for the simultaneous transmission condition per FCC KDB 447498 and RSS-102. A Formula is also showed below: The procedure rules are provided in 2.3 in this document. As the module manufacturer is still taking responsibility for the compliance of this module, if you have any changes mentioned above, you must advise and get the help from us with the contact information as shown below 2.12.
2.7 Antennas
This radio transmitter has been approved by Federal Communications Commission to
operate with the antenna types listed below, with the maximum permissible gain indicated.
FCC ID: 2BM2K-M4P
Antenna types not included in this list that have a gain greater than the maximum gain
indicated for any type listed are strictly prohibited for use with this device.
Radios
Dipole Antenna
LoRa
1.34dBi
2.8 Label and compliance information
The final end product must be labeled in a visible area with the following” Contains FCC ID: 2BM2K-M4
2.9 Information on test modes and additional testing requirements
Host manufacturer is strongly recommended to confirm compliance with FCC requirements for the transmitter when the module is installed in the host. Additional testing requirements should be taking into account for different operating conditions for the transmitter function. If this module is operated as a stand-alone modular in a host:
Radiated spurious emission per FCC Part 15.247, RSS-247 The host should be operated in all its normal mode with the modular transmitter active. Please follow 2.11 in this document to obtain a best radio engineer design.
If this module is operated as multiple simultaneously transmitting modules in a host: Foundation frequency power, Radiated spurious emission per FCC Part 15.247 and RSS-247.
Conducted spurious emission and conducted power per FCC part 15.247 and
RSS-247. Please contact the modular manufacturer through the contact information
shown below 2.12 to get the test software. This module should be operated in transmitter mode with other transmitter
for the simultaneous condition. Please follow 2.11 in this document to obtain a best radio engineer design. The procedure rules are provided in 2.3 in this document. As the module
manufacturer is still taking responsibility for the compliance of this module, if you have any changes mentioned above, you must advise and get the help from us with the contact information as shown below 2.12.
2.10 Additional testing, Part 15 Subpart B disclaimer
Host manufacturer is responsible for compliance of the host system with module installed with all other applicable requirements for the system such as Part 15 B.
2.11 Note EMI Considerations EMI consideration for transmitting simultaneously: This module is stand-alone modular. If the end product has multiple certified modules integrated in a host and transmitting simultaneously: When after radiated emission testing, if there are no additional emissions generated due to simultaneoustransmission operations compared to single transmitter operations testing, it is not necessary to file the additional simultaneous transmission test data. FCC class II permissive changes is no necessary. However, RF exposure for transmitting simultaneously also needed, please refer to 2.6 in this document.
To obtain better engineer design while installing this module: It is recommended to place the module as close as possible to the edge of the baseplate. If conditions permit, make the antenna feed point closest to the edge of the baseplate. Please ensure that the module is not covered by any metal shell. Do not lay copper, wire, or place components in the antenna area of the module PCB.
2.12 How to make changes Only the module grantee is permitted to make permissive changes. If the host integrator is expected to install the module in a way different from this manual or want to change the module, please contact:
Company: Shenzhen Navynav Technology Co., Ltd. Address: Room 502, Han’s Laser Technology Centre Shennan Ave No.9988, Nanshan District, Shenzhen, Guangdong Province, China Email: 157381769@qq.com
Documents / Resources
 | navynav M4 Wireless Data Transceiver [pdf] Owner's Manual 2BM2K-M4, 2BM2KM4, M4 Wireless Data Transceiver, M4, Wireless Data Transceiver, Data Transceiver, Transceiver |