e-Yantra Team eYFi-Mega User manual

Hardware Manual
for eYFi-Mega Development Board
Produced by: e-Yantra Team
https://e-yantra.org/products/eyfi-mega
Version: 0.1
Dated: December 14, 2019

About this Document
This document is created for all developers wanting to work with the eYFi-Mega
development board. It provides the detailed description and specification of the
board.
Revision History
For revision history of this document, please refer to the Appendix A.
Disclaimer and Copyright Notice
Information in this document, including URL references, is subject to change with-
out notice. This document is provided as is with no warranties whatsoever, includ-
ing any warranty or merchantability, non-infringement, fitness for any particular
purpose, or any warranty otherwise arising out of any proposal, specification or
sample. All liability, including liability for infringement of any proprietary rights,
relating to use of information in this document is disclaimed. No licenses express
or implied to any intellectual property rights are granted herein. The e-Yantra Prod-
ucts logo is a registered trademark.
Copyright ©2019 e-Yantra, ERTS Lab, CSE Dept., IIT Bombay, India.
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Table of Contents
1 Board Overview 5
1.1 Kit Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.2 Quick Start .................................. 6
1.2.1 Getting Started . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.2.2 System Requirements . . . . . . . . . . . . . . . . . . . . . . . 6
1.2.3 Development Toolchains . . . . . . . . . . . . . . . . . . . . . 6
1.3 Features .................................... 7
1.4 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2 Hardware Description 8
2.1 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.1.1 ATmega2560 micro-controller . . . . . . . . . . . . . . . . . . 10
2.1.2 ESP32 micro-controller . . . . . . . . . . . . . . . . . . . . . . 10
2.1.3 16 MHz crystal . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.1.4 LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.1.5 Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.1.6 ICSP connector . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.1.7 GPIO1 header . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.1.8 GPIO2 header . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.1.9 INTx header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.1.10 ADCx header . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.1.11 I2C header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.1.12 UART header . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.1.13 SPI header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.1.14 PWM header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.1.15 ESP32 GPIO header . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.1.16 Micro-USB connector . . . . . . . . . . . . . . . . . . . . . . . 17
3 Power Management 19
3.1 5V DC Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.2 3.3V header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.3 EXT_PWR header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4 References 20
Appendices 21
A Revision History 21
B Flashing Boot-loader on ATmega2560 22
2

C Flashing Boot-loader on ESP32 25
3

List of Figures
1 eYFi-Mega development board . . . . . . . . . . . . . . . . . . . . . . 5
2 Block diagram of eYFi-Mega . . . . . . . . . . . . . . . . . . . . . . . . 8
3 Functional diagram of eYFi-Mega . . . . . . . . . . . . . . . . . . . . . 9
4 eYFi-Mega Pinout Diagram for ATmega2560 . . . . . . . . . . . . . . . 14
5 eYFi-Mega Pinout Diagram for ESP32 . . . . . . . . . . . . . . . . . . 18
6 Device Programming dialog box in Atmel Studio 7 . . . . . . . . . . . 23
7 Fuse settings to be done . . . . . . . . . . . . . . . . . . . . . . . . . . 23
8 All OK message after programming the Fuses . . . . . . . . . . . . . . 24
List of Tables
1 Specifications of eYFi-Mega development board . . . . . . . . . . . . 7
2 Functional Diagram of eYFi-Mega . . . . . . . . . . . . . . . . . . . . . 9
3 Partition Table of on-board ESP32 micro-controller . . . . . . . . . . 10
4 Patterns of Wi-Fi status LED with various states of the board . . . . . 11
5 Function of Switches S1, S2 and S3 . . . . . . . . . . . . . . . . . . . . 13
6 Switch positions for various programming modes . . . . . . . . . . . 13
7 Revision History of the document . . . . . . . . . . . . . . . . . . . . . 21
4

1
Board Overview
Figure 1: eYFi-Mega development board
The eYFi-Mega board provides an flexible and affordable way for users to try out new
concepts and build prototype projects with the 8-bit ATmega2560 micro-controller in
TQFP100 package and the 32-bit ESP32 micro-controller, choosing from the various
combinations of performance, power consumption and features.
The eYFi-Mega board does not require any specialized hardware for programming as it
comes with pre-installed bootloader file thus, the firmware on ATmega2560 and ESP32
can be easily updated either wired / wirelessly (Over-The-Air).
The eYFi-Mega board comes with the comprehensive support of Arduino Programming
Language and Espressif IoT Development Framework (esp-idf) which is the official de-
velopment framework for the ESP32 chip.
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The eYFi-Mega board comes with the pre-defined group of pins having the same func-
tionality, making it easier for the developer to access and work with it.
1.1 Kit Contents
The eYFi-Mega Kit contains the following items:
• eYFi-Mega Development Board
• Interface Board
• USB micro-B plug to USB-A plug cable
1.2 Quick Start
For more information on the eYFi-Mega board and to access the documentation and
tutorials, visit https://e-yantra.org/products/eyfi-mega.
1.2.1 Getting Started
Follow the sequence below to configure the eYFi-Mega and launch the demo software:
• Connect the eYFi-Mega board to a PC with a USB micro-B plug to USB-A plug
cable through USB connector to power the board. The red LEDs AVR_ON and
ESP_ON should light up.
• The RGB LED should light up and blink Red, Green and Blue colors in a sequence
at the intervals of a second.
• Press button USER_SW (User Switch).
• Observe the change in colors on the RGB LED, by pressing the button USER_SW. It
will glow the colors Yellow, Cyan, Magenta, Red, Green, Blue in a sequence. After
this, the RGB LED will reset to the blinking of Red, Green and Blue color in the
interval of a second.
1.2.2 System Requirements
• Linux: Ubuntu LTS 16.04 and 18.04
• USB micro-B plug to USB-A plug cable
1.2.3 Development Toolchains
• eY-IDE (Visual Studio Code extension)
• AVR-GCC
• ESP-IDF
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1.3 Features
Your eYFi-Mega development board includes the following features:
• Dual Micro-controller Board 8-bit ATmega2560 & 32-bit ESP32
• High Output Power 12.5 W (5V, 2.5A)
• Wi-Fi Protocol: 802.11 b/g/n (802.11n up to 150 Mbps),
Frequency Range: 2.4 GHz 2.5 GHz
• Bluetooth Low Energy Protocol: Bluetooth v4.2 BR/EDR and
BLE specification
• On-board File Storage 700 KB SPI-Flash File System (expandable up
to 3 MB)
• Compatible with FreeRTOS Both micro-controllers are capable of running
FreeRTOS, ESP32 runs FreeRTOS out-of-the-
box
• Arduino Programming Language Both micro-controllers can be programmed
using Arduino Programming Language
1.4 Specifications
Table 1 summarizes the specifications of the eYFi-Mega board.
Table 1: Specifications of eYFi-Mega development board
Parameter Value
Board Supply Voltage 4.75 VDC to 5.25 VDC from USB Micro-B cable (connected to a PC)
7.0 VDC to 21.0 VDC from External Power Supply
Dimensions 107.95 mm x 64.01 mm x 24 mm (L x W x H)
Break-out power output 3.3 VDC (800 mA max)
5.0 VDC (2.5 A max)
RoHS status Compliant
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2
Hardware Description
Figure 2: Block diagram of eYFi-Mega
The eYFi-Mega board includes ATmega2560 and ESP32 micro-controllers and a range
of useful peripheral features (as the block diagram in Figure 2). This chapter describes
how these peripherals operate and interface to the micro-controller.
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Figure 3: Functional diagram of eYFi-Mega
Table 2-1 summarizes the parts of the eYFi-Mega board with respect to the Figure 3.
Table 2: Functional Diagram of eYFi-Mega
# Component Name # Component Name
1 ATmega2560 micro-controller 14 PWM header
2 INTx header 15 EXT_PWR header
3 ADCx header 16 S3 switch
4 I2C header 17 3.3 V header
5 GPIO1 header 18 S1 switch
6 USER_SW push button 19 TX LED and RX LED
7 16 MHz crystal 20 ESP32 GPIO header
8 AVR_RESET push button 21 S2 switch
9 GPIO2 header 22 Micro-USB connector
10 UART header 23 Wi-Fi Status LED
11 AVR_ON LED 24 ESP_ON LED
12 ICSP connector 25 ESP32 micro-controller
13 SPI header 26 ESP_RESET push button
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