Myriota Module M224 Maker’s Guide MYRIOTA-TEC-179 26 February 2021 ©Myriota Pty Ltd
Revision History Rev Date Description of Change 1.0 February 2021 Initial version 1.1 February 2021 Updated with celltech Suggestions Related Documentation Find the latest versions of all Myriota documentation at developer.myriota.com How to Contact Us Technical Support Sales Support Myriota Online developer.myriota.com sales@myriota.com myriota.com support@myriota.com 2 MYRIOTA-TEC-179-1.
Disclaimer The information contained in this document (collectively, the “Information”) is provided to you (both the individual receiving this document and any legal entity on behalf of which such individual is acting) (“You” and “Your”) by Myriota Pty Ltd for information purposes only. — Information in this document is provided solely to enable system and software implementers to use Myriota Pty Ltd products.
Table of Contents 1 - System Overview 7 1.1 - Features 7 Exceptional Battery Life 7 ARM Cortex-M4 core 7 Inter-Integrated Circuit Interface (I2C) 7 Universal Asynchronous Receiver/Transmitter (UART) 7 Serial Peripheral Interface (SPI) 7 Low Energy Universal Asynchronous Receiver/Transmitter (LEUART) 7 Pulse Counter (PCNT) 8 Analog to Digital Converter (ADC) 8 Pre-Programmed UART Bootloader 8 1.2 - Safety and Compliance 8 1.2.1 - FCC Compliance 8 1.2.
2.6 - General Environmental Characteristics 14 3 - Electrical Information 15 Typical Values 15 Absolute Maximum Ratings 15 3.1 - Block Diagram 15 3.2 - Module Pin Assignment 16 3.3 - Power Consumption 19 3.4 - Electrical Specifications 20 Table 5: General Operating Conditions 20 Table 6: General Purpose Input Output 20 Table 7: Analog Digital Converter (ADC) 20 Table 8: I2C 21 Table 9: Temperature Sensor 21 Table 10: Test Conditions 23 4 - Radio Elements 24 4.
5 - Getting Started 30 Visit the Myriota Developer Site 30 6 MYRIOTA-TEC-179-1.
1 - System Overview The Myriota M2-24 Module (“the Module”) employs smart power features and onboard edge computing, combined with the super low bandwidth Myriota Network, to provide an ideal IoT communications solution for remote devices. 1.
Pulse Counter (PCNT) — The Pulse Counter (PCNT) can be used for counting pulses on an input while the Module is in sleep mode. It can also wake up the Module from sleep mode when a prespecified number of pulses have been counted Analog to Digital Converter (ADC) — 12-bit ADC supporting VIO_REF, 2.5V or 1.25V as reference voltages Pre-Programmed UART Bootloader — The pre-programmed bootloader can be used to program the flash, retrieve Module information and dump logs 1.2 - Safety and Compliance 1.2.
1.2.2 - Industry Canada Compliance English Under Industry Canada regulations, this radio transmitter may only operate using an antenna of a type and maximum (or lesser) gain approved for the transmitter by Industry Canada. To reduce potential radio interference to other users, the antenna type and its gain should be so chosen that the equivalent isotropically radiated power (e.i.r.p.) is not more than that necessary for successful communication.
1.2.3 – Host Integration Compliance 2.2 This device was evaluated to, and complies with, FCC 47 CFR Part 25 Subpart C and ISED RSS-170 2.3 This device shall only be used in the manner intended to be used and in accordance with FCC 47 CFR Part 25 Subpart C and ISED RSS-170. 2.4 This device is certified as an FCC Single Modular Approval and ISED Modular Approval (MA) 2.5 See Section 2.5 for trace design considerations 2.6(1) This device is approved for use with mobile and fixed applications.
2 - Physical Specification The Myriota M2-24 Module is designed to, and must be installed within an enclosed host system. With appropriate external connections, the host system and host system enclosure can be designed to meet full transceiver regulatory tests. 2.1 - Module Dimensions and Layout The Myriota M2-24 Module dimensions and weight are outlined in Table 1, and in Figure 1 for illustrative purposes. Table 1: M2-24 Module Dimensions and Approximate Weight Length 33.91 mm Width 20.
2.3 - Handling Information Moisture Sensitivity Level (MSL): 3 per IPC/JEDEC standard J-STD-020. Avoid washing as moisture can be trapped under the shield. Electrostatic Discharge Caution: The module contains static-sensitive components and should be handled with care. The following precautions are recommended to avoid static damage. ● ● ● Avoid touching pins. Always hold modules by its edges Handle modules in areas with adequate grounding Keep modules in trays/ESD bags until ready for assembly 2.
2.5 - PCB Layout Considerations ● The PCB trace connecting the Myriota Module’s RF PORT to the antenna needs to be a controlled impedance, 50-ohm transmission line. Microstrip is recommended, but other types of transmission lines would be acceptable, depending on the trade-offs that are most important for a given application. ● The exact geometries of the 50-ohm microstrip depend on the characteristics of the PCB substrate that is being used in the application, i.e.
● Ground pads of the Myriota Module should be connected directly to the ground reference plane with the ground vias placed as close to the Myriota Module pads as is practical. ● Power supplied to the Myriota Module should be clean and isolated from potential noise sources originating from the application circuitry. This can be achieved through the use of filters or linear regulation in the power feed to the Myriota Module.
3 - Electrical Information Typical Values The typical data are based on ambient temperature TAMB = 25°C and power supply voltage VEXT = 3.6 V. Absolute Maximum Ratings The absolute maximum ratings are stress ratings, and functional operations under such conditions are not guaranteed. Stress beyond the limits specified in the table below may affect device reliability or cause permanent damage to the device. 3.1 - Block Diagram Figure 2: A simplified block diagram of the Myriota Mx-2x series.
3.2 - Module Pin Assignment The Myriota M2-24 Module features 58 pins, as depicted in Figure XX, and Table XX. Figure 3: M2-24 Module Pin Assignment 16 MYRIOTA-TEC-179-1.
Table 3: Pin Descriptions Number Name Description / Alternative Functionality 1 VIO_REF Voltage reference output for all external devices 2 BAND Read-only, do not connect. High on M1 variant and low on M2 variant 3 GND Ground 4 VEXT Power supply 5 GND Ground 6 ADC1 ADC port 1. GPIO 7 GND Ground 8 ADC0 ADC port 0. GPIO 9 GND Ground 10 PULSE1 Pulse counter. GPIO 11 PULSE0 Pulse counter. GPIO 12 UART0_RTS UART0 RTS. GPIO 13 NRST Reset input, active low.
26 GND Ground 27 RF_PORT RF port for both input and output 28 GND Ground 29 GND Ground 30 GND Ground 31 GND Ground 32 RF_TEST2 Reserved, do not connect 33 GPIO4 GPIO 34 GPIO5 GPIO 35 GPIO6 GPIO 36 GND Ground 37 GND Ground 38 VUSB USB 5.0 V VBUS input. Reserved, do not connect 39 GND Ground 40 GND Ground 41 GPIO1_WKUP GPIO.
53 GPIO7 GPIO 54 UART0_CTS UART0 CTS. GPIO 55 UART0_TX UART0 TX, output. Bootloader TX 56 UART0_RX UART0 RX, input. Bootloader RX 57 LEUART_RX LEUART RX, input 58 LEUART_TX LEUART TX, output 3.3 - Power Consumption The Module is designed with a very low power consumption profile, and is designed to attain multi-year battery life with two “AA'' battery cells. Table XX lays out the power consumption for the Module. Table 4: Specific average power consumption measured at 25ºC Mode 3V 3.
3.4 - Electrical Specifications The electrical parameters for the Module are detailed in the tables below. Table 5: General Operating Conditions Parameter Minimum Typical Maximum Unit Operating temperature -30 - 70 ºC Clock frequency - - 48 MHz VEXT 3.0 3.6 V VIO_REF (non sleep mode) - 3.3 - V VIO_REF (sleep mode) - VEXT-0.2 - V 100 mA VIO_REF output current Table 6: General Purpose Input Output Parameter Minimum Typical Maximum Unit Input low voltage - - 0.
Input voltage range 0 - Reference voltage V Resolution - 12 - bit Input capacitance - 2 - pF Input ON resistance 1 - - MOhm Input RC filter resistance - 10 - kOhm Input RC filter/decoupling capacitance - 250 - fF ADC Clock Frequency - 13 3 MHz Conversion and acquisition time 87 - - ADCCLK Cycles non-linearity (INL) - ±1.2 ±3 LSB Offset voltage -3.5 0.
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Table 10: Test Conditions Parameter Minimum Typical Maximum Unit Storage temperature -55 - 150 ºC External supply voltage (VEXT) 0 - 3.6 V Voltage on any I/O pin -0.3 - VIO_REF+0.3 V 23 MYRIOTA-TEC-179-1.
4 - Radio Elements 4.1 Operational Frequencies The Myriota M2-24 variant module transmits and receives on UHF. A single antenna can be used to provide both channels. Table 11: Operational Frequencies. Frequency UHF Transmission 399.9 - 400.05 MHz UHF Receive 400.15 - 401 MHz 4.2 - Antenna Connection This Module has no integrated connector. All RF activity is operated over Pin 27. Methods by which a temporary may be used for testing are detailed in Section 4.
(DCR) from Taiyo Yuden are a good choice. The inductor’s self resonant frequency (SRF) should be higher than the operating frequency. An example of a 120 nH inductor is HK1005R12J-T. Its specifications are: DCR=1.6 Ohm; Q=8 @ 100 MHz; SRF=600 MHz. Q scales approximately by √f , so in this example the inductor would have a Q of about 16 at 400 MHz. ● Often an RF connector is added to assist testing or developing a PCB.
4.4 - Antenna Requirements The following sections define the network requirements on both the transmit and receive antennas for the M2-24 Myriota Module. The requirements are defined in terms of recommended antenna gains, assuming the device has clear sky view in all directions. An antenna that exceeds the recommended gain requirement will result in increased performance of your device. Likewise, an antenna that has less gain will result in reduced device performance.
Comparing the gain of the antenna to the recommended minimum, you can see that it either meets or exceeds the requirement at mid elevations, with diminished performance at high and very low elevations. Again this is representative of the characteristics expected from an electrically small monopole with vertical polarisation. Depending on system requirements, the reduced performance at high and very low elevations can be considered acceptable. Elevation (deg.
4.4 - RF Characteristics Table 14 lays out the RF characteristics of the Module. Table 14: Radio Characteristics. Parameter Minimum Transmission duration Typical Maximum 260 Unit ms Transmission interval 5 s UHF TX frequency 399.9 - 400.05 MHz UHF RX frequency 400.15 - 401 MHz LPD frequency 433 - 435 MHz UHF output power - - 28 dBm LPD output power - - 14 dBm 4.
Figure 15: The SAM-M8Q-0-10 GNSS module The SAM-M8Q-0-10 module has a backup voltage supply (V_BCKP). When the power supply to the module is off, V_BCKP supplies the real-time clock (RTC) and battery-backed RAM (BBR). Use of valid time and the GNSS orbit data at start-up will improve the GNSS performance, i.e. hot starts and warm starts. If no backup battery is connected, the module performs a cold start at power-up.
5 - Getting Started Visit the Myriota Developer Site Once you are ready to begin developing the software for the Module, head over to the Myriot Developer Site at: https://developer.myriota.com/ Figure XX: The Myriota Developer Site 30 MYRIOTA-TEC-179-1.
