MicroRidge MICRO-RM2.4 User manual

All rights reserved. No parts of this work may be reproduced in any form or by any means - graphic, electronic, or
mechanical, including photocopying, recording, taping, or information storage and retrieval systems - without the written
permission of the publisher.
Products that are referred to in this document may be either trademarks and/or registered trademarks of the respective
owners. The publisher and the author make no claim to these trademarks.
While every precaution has been taken in the preparation of this document, the publisher and the author assume no
responsibility for errors or omissions, or for damages resulting from the use of information contained in this document or
from the use of programs and source code that may accompany it. In no event shall the publisher and the author be liable
for any loss of profit or any other commercial damage caused or alleged to have been caused directly or indirectly by this
document.
Version: 1.3.9
Printed: Wednesday, December 12, 2018 at 1:22 PM in Sunriver, Oregon.
MicroRidge 2.4 GHz Radio Module
Copyright © 2014-2018 MicroRidge Systems, Inc.

IContents
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
Table of Contents
Chapter 1 1 ...................................................................................................................................Introduction
Chapter 2 3 ...................................................................................................................................Features
Chapter 3 4 ...................................................................................................................................Related Documents
Chapter 4 5 ...................................................................................................................................Specifications
...................................................................................................................................
Atmel Documentation 5
...................................................................................................................................
Dimensions 7
...................................................................................................................................
Solder Paste Mask 10
...................................................................................................................................
Pin Configuration 11
...................................................................................................................................
Soldering 13
Chapter 5 14 ...................................................................................................................................Serial Number
Chapter 6 15 ...................................................................................................................................Wireless Library
Chapter 7 16 ...................................................................................................................................Application Board Design
Chapter 8 18 ...................................................................................................................................Ordering Information
Chapter 9 19 ...................................................................................................................................Radio Certification
Chapter 10 22 ...................................................................................................................................Contact MicroRidge
Chapter 11 23 ...................................................................................................................................Revision History

Introduction 1
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
1 Introduction
The MICRO-RM2.4 Radio Module from MicroRidge Systems is a small wireless module based
on the Atmel ATmega2564RFR2 microcontroller. The ATmega2564RFR2 is a low-powered
CMOS 8-bit microcontroller based on the AVR enhanced RISC architecture combined with a high
data rate transceiver for the 2.4 GHz ISM (industrial, scientific and medical) band.
The MICRO-RM2.4 contains an on-board chip antenna. The module contains radio certifications
for FCC, IC and EU (CE). No additional RF testing is required as long as the application of the
MICRO-RM2.4 follows the approved certifications.
The small size of the MICRO-RM2.4 module allows it to be used in small and compact products.
The module measures 12 x 20.75 x 3 mm (.472 x .817 x .118 inches). The module requires a
power supply of 1.8 to 3.6 volts DC. This voltage range allows the module to be powered by a
single 3 volt coin cell or two 1.5 volt batteries.
Radio Module Images
The photos below show the top and bottom views of the radio module. The 2 large gold pads
shown in the bottom view are the ground pads discussed in the Dimensions section .
Isometric View
Top View
Bottom View
7

Introduction 2
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
Basic Block Diagram
A basic block diagram of the MICRO-RM2.4 Radio Module is shown below. Refer to the Atmel
ATmega644/1284/2564RFR2 documentation for block diagrams with greater detail.
4

Features 3
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
2 Features
The features of the MICRO-RM2.4 Radio Module are numerous and allow the module to be used
in many low powered short range applications. The primary features of this module are as
follows:
§ Ultra compact size: 12 x 20.75 x 3 mm (.472 x .817 x .118 inches)
§ Built-in 32.768 kHz crystal for low power and deep sleep modes
§ Built-in 16 MHz crystal for 2.4 GHz transceiver and AVR microcontroller
§ Power supply voltage of 1.8 to 3.6 VDC
§ Typical power consumption:
o0.75 m A in sleep mode (transceiver in Sleep and AVR in Power Save/Down mode)
o14.5 ma in TX mode at 3.5 dBm
o12.5 ma in RX mode
§ Memory resources:
o256K bytes In-System Self-Programmable Flash
o8K bytes EEPROM
o32K bytes SRAM
§ High performance RF-CMOS 2.4 GHz radio transceiver targeted for IEEE®802.15.4™,
ZigBee™, IPv6, 6LoWPAN, RF4CE, SP100, WirelessHART™ and ISM applications.
§ TX/RX 128 byte frame buffer
§ TX output power from -17 dBm to 3.5 dBm
§ Receiver sensitivity = -100 dBm
§ 14 RF Channels (11 to 25, channel 14 is reserved for internal use)
§ Serial bootloader
§ Interface connections:
o30 I/O ports
o2 RS-232 serial ports
oJTAG programming connection
oI2C
§ High performance low power AVR®8-bit microcontroller
§ ROHS complainant
§ Extensive documentation and software resources available on the Atmel web site

Related Documents 4
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
3 Related Documents
Additional information is available about the MICRO-RM2.4 Radio Module components and
supporting software from the following sources:
§ A complete description of the ATmega2564RFR2 microcontroller used in the module is
available on the Atmel web site (www.atmel.com). The document describing this
microcontroller is ATmega644/1284/2564RFR2 42073B-MCU Wireless. The document
number (42073B-MCU) is updated by Atmel when changes are made to the document.
§ Atmel also has additional documentation available that may be helpful in developing
wireless applications for the MICRO-RM2.4 module.
§ The MicroRidge MICRO-RM2.4 Wireless Communication Library (RM2.4 Library) is
available to assist in the development of firmware for the MICRO-RM2.4 Radio Module. In
order to use the RM2.4 Library, you must purchase Radio Modules that have the library
support enabled. This library is only supported on specific versions of the IAR Embedded
Workbench for the AVR microcontroller. Refer to the Wireless Library section in this
manual for more information.
§ Additional documentation and information dealing with the MICRO-RM2.4 Radio Module
will be available at www.MicroRidge-RM.com during the 3rd quarter of 2015.
15

Specifications 5
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
4 Specifications
The specifications section consists of 4 areas:
Atmel Documentation This section contains 3 of the tables from the Atmel
ATmega644/1284/2564RFR2 documentation. The
complete Atmel document is over 600 pages in length. In
order to fully understand the radio module and how to work
with it, you must become familiar with this Atmel document.
Dimensions The dimensions for the MICRO-RM2.4 Radio Module, pad
locations and bottom side ground pads are presented in
this section.
Pin Configuration The pin connections available on the MICRO-RM2.4 Radio
Module are listed in this section.
Soldering A soldering profile is shown in this section.
4.1 Atmel Documentation
For the complete specifications for the Atmel ATmega2564RFR2 radio transceiver refer to
ATmega644/1284/2564RFR2 documentation . The information shown below is only a few of
the multiple tables from the Atmel documentation. Refer to the Atmel documentation for the test
conditions and references shown in the tables.
General RF Specifications
4

Specifications 6
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
Transmitter characteristics
Current Consumptions Specifications

Specifications 7
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
4.2 Dimensions
Board Dimensions
The dimensions for the MICRO-RM2.4 Radio Module are given below. All of the dimensions are
in mm. The thickness of the module from the bottom of the module to the top of the RF shield is
3 mm. The pad spacing is 1 mm and the pad width is 0.7 mm.
Board Dimensions (mm) and Solder Pad Placement

Specifications 8
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
Solder Pad Placement
The recommended placement of the solder pads on the application board is shown below. The
2 large pads are ground pads and they are discussed in the Ground Pads section on the next
page. All dimensions are in mm.

Specifications 9
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
Ground Pads
The bottom of the module contains 2 ground (GND) pad areas that can be used to help secure
the module to the circuit board. In a rough environment, we have seen delamination problems
with this type of module board. When adhesive was used to help secure the module board to
the application circuit board, we no longer had any delamination problems between the module
and application circuit boards. In the stuffing process, the board house can use an adhesive to
help secure the wireless module to the application circuit board or solder the ground pads to the
application circuit board..
The 2 ground pads are available on the bottom side of the wireless module. These ground pads
are shown in red and labeled A and B. These 2 pad areas are part of the bottom ground plane.
Location of the Ground Pads on the Bottom of the Wireless Module
The size and location of the ground pads are shown in the following table.
Ground
Pad
Size
Distance from Upper Left Corner
Width, mm
Height, mm
Horizontal, mm
Vertical, mm
A
3.25
2.50
6.50
5.50
B
2.625
5.00
14.75
2.50

Specifications 10
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
4.3 Solder Paste Mask
The solder mask for the pads around the edge of the Radio Module should match the size of the
solder pads. The solder mask for the ground pads A and B, should made up of several smaller
solder mask regions. If you create solder masks that are the same size as the ground pads A
and B, you may see a tendency for the Radio Module to be raised off of the circuit board.
The following table details the dimensions and placement of the recommended solder masks for
pads A and B. All dimensions are in mm.
Ground
Pad
Pad
Size
Number
of Solder
Mask Pad
Size of
Pads
Gap Around Pads
Solder
Coverage
Outside
Inside
A
2.5 x 3.25
2
1.9 x
1.125
.3
.4
52.6%
B
5 x 2.625
3
1.2 x
2.025
.3
.4
55.5%

Specifications 11
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
4.4 Pin Configuration
The pin connections for the MICRO-RM2.4 Radio Module are show below. For a complete
description of each pin refer to the Atmel ATmega644/1284/2564RFR2 documentation.
MICRO-RM2.4 Pin Connections
Module
Pin
Pin
Name
Description
1
GND
Ground (connected to AVSS_RFP, AVSS_RFN, DVSS & AVSS)
2
RESET
Reset input (active low). The radio module also contains a 100K
pullup resistor connected between this pin and VCC.
3
PG1
Port PG1
4
PD5
Port PD5 (alternate function XCK1)
5
PD4
Port PD4 (alternate function ICP1)
4

Specifications 12
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
Module
Pin
Pin
Name
Description
6
PD1
Port PD1 (alternate functions SDA & INT1)
7
PD0
Port PD0 (alternate functions SCL & INT0)
8
VCC
1.8 to 3.6 VDC (connected to DEVDD & EVDD)
9
PB5
Port PB5 (alternate functions OC1A & PCINT5)
10
PD2
Port PD2 (alternate functions RXD1 & INT2)
11
PD3
Port PD3 (alternate functions TXD1 & INT3)
12
PD6
Port PD6 (alternate function T1)
13
PB0
Port PB0 (alternate functions SSN & PCINT0)
14
VCC
1.8 to 3.6 VDC (connected to DEVDD & EVDD)
15
PB4
Port PB4 (alternate functions OC2A & PCINT4)
16
PB1
Port PB1 (alternate functions SCK & PCINT1)
17
PB2
Port PB2 (alternate functions MOSI, PDI & PCINT2)
18
PB3
Port PB3 (alternate functions MISO, PDO & PCINT3)
19
PB6
Port PB6 (alternate functionsOC1B & PCINT6)
20
PB7
Port PB7 (alternate functions OC0A, OC1C & PCINT7)
21
PE0
Port PE0 (alternate functions RXD0 & PCINT8)
22
PE1
Port PE1 (alternate function TXD0)
23
PE2
Port PE2 (alternate functions XCK0 & AIN0)
24
PE3
Port PE3 (alternate functions OC3A & AIN1)
25
PE4
Port PE4 (alternate functions OC3B & INT4)
26
PE5
Port PE5 (alternate functions OC3C & INT5)
27
PE7
Port PE7 (alternate functions ICP3, INT7 & CLK)
28
VCC
1.8 to 3.6 VDC (connected to DEVDD & EVDD)
29
PF2
Port PF2 (alternate function ADC2)
30
PF1
Port PF1 (alternate function ADC1)
31
PF0
Port PF0 (alternate function ADC0)

Specifications 13
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
Module
Pin
Pin
Name
Description
32
PF7
Port PF7 (alternate functions JTAG TDI & ADC7)
33
PF6
Port PF6 (alternate functions JTAG TDO & ADC6)
34
PF5
Port PF5 (alternate functions JTAG TMS & ADC5)
35
PF4
Port PF4 (alternate functions JTAG TCK, PF3 & ADC3)
36
GND
Ground (connected to AVSS_RFP, AVSS_RFN, DVSS & AVSS)
--
PD7
Port PD7. Do not use. This ports is used internally by the wireless
module. This pin must remain at the default state of input without
pullup.
--
TST
Connected to GND in the wireless module.
--
CLKI
Connected to GND in the wireless module.
--
TOSC1
Connected to 32.768 KHz crystal in the wireless module.
--
TOSC2
Connected to 32.768 KHz crystal in the wireless module.
--
XTAL1
Connected to 16 MHz crystal in the wireless module.
--
XTAL2
Connected to 16 MHz crystal in the wireless module.
4.5 Soldering
The following J-STD-020C compliant soldering profile is recommended for the MICRO-RM2.4
Radio Module. Since the FCC and IC IDs are etched into the RF shield, there is no concern
about heat from the soldering process damaging a label that contains this ID information.
Profile Feature
Values
Average ramp-up rate (217°C to peak)
3°C/s max
Preheat temperature 175°C ±25°C
180s max
Temperature maintained above 217°C
60s to 150s
Time within 5°C of actual peak temperature
20s to 40s
Peak temperature range
260°C
Ramp-down rate
6°C/s max
Time within 25°C to peak temperature
8 minutes

Serial Number 14
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
5 Serial Number
The ATmega2564RFR2 contains 3 flash pages that are dedicated for User Signature data.
These signature pages are isolated from the main flash and will not be cleared by a Chip Erase
command. Special commands must be used to erase and write data to User Signature pages via
the Parallel and JTAG interface. Each User Signature page contains 256 bytes for a total of 768
bytes
The MICRO-RM2.4 Radio Module uses page 1 of the User Signature pages to store information
about the Radio Module. The information on page 1 is written by MicroRidge during module
testing & verification prior to shipping a module to the customer.
One of the items in this User Signature page is a unique 64-bit serial number. You must not
attempt to change any of the information on page 1 of the User Signature data.
The MICRO-RM2.4 Wireless Communications Library can read the 64-bit serial number and
return the results as 8 8-bit bytes or 16 4-bit hex characters. The address of the serial number is
as follows:
§ 0x08 = Address of serial number expressed as 8 8-bit bytes
§ 0x10 = Address of serial number expressed as 16 4-bit hex characters
15

Wireless Library 15
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
6 Wireless Library
In order to use the wireless communications functions of the MICRO-RM2.4 Radio Module, your
firmware must interact with the I/O ports that control the 2.4 GHz transceiver that is part of the
Radio Module. You can refer to the various Atmel documents and resources to learn how to get
access to the wireless functions or you may be able to use the MICRO-RM2.4 Wireless
Communication Library (RM2.4 Library) that MicroRidge has developed. The RM2.4 Library was
developed to support point-to-point communications between a transmitter and a receiver.
MicroRidge has been using a version of these libraries since 2011.
The library files consist of a compiled library file and a header file for your application. The
library was compiled with the IAR Embedded Workbench for the AVR microcontroller. Only the
current version of the IAR compiler is supported for the RM2.4 Library.
The RM2.4 Library for the MICRO-RM2.4 Radio Module will be released in the 3rd quarter of
2015. These library files will be available at www.MicroRidge-RM.com.

Application Board Design 16
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
7 Application Board Design
Normally, chip antennas are more tolerant of the board and enclosure materials. However, the
recommendations for the radio module placement on the application PCB still apply. The radio
module should be placed along an edge of the application PCB as shown below.
Module placed along top
edge of PCB.
Module placed along top
edge of PCB.
Module placed in center
portion of PCB.
Not an acceptable design.
Mounting Information
In general, via holes and traces should not be placed on the application PCB upper layer in the
area occupied by the radio module module. The exception to this is if you are soldering the
ground pads to the PCB board, you can use via holes and/or traces to connect the pads to
the ground. Be careful that you do not place any via holes or traces adjacent to non-ground
circuits.
The ground connections along the edges of the radio module should be grounded by via holes
located as close as possible to the ground connections on the radio module.
Via Placement
The board design should prevent propagation of microwave fields inside the board material.
Electromagnetic waves of high frequency may penetrate the board thus making the edges of the
board radiate, which may distort the antenna pattern. To eliminate this effect, via holes should be
placed around the board's edges. A common rule of thumb is to make the via spacing less than
λ/20 at the maximum operating frequency. For the MICRO-RM2.4 Radio Module, the wavelength
at 2.4 GHz is 125 mm and the maximum via spacing would be 6.25 mm.
9

Application Board Design 17
Copyright © 2014-2018 MicroRidge Systems, Inc.
MicroRidge 2.4 GHz Radio Module
Version 1.3.9
Other Recommendations
§ Metal enclosure should not be used.
§ Low profile enclosures might affect antenna performance.
§ Avoid placing high profile components next to antenna.
§ Radio module should not be placed next to other electronics which might interfere with the
2.4 GHz frequency band.