e-Yantra Team eYFi-Mega, Руководство по оборудованию

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2.1 Functional Description
2.1.1 ATmega2560 micro-controller
ATmega2560 micro-controller is one of the most rich feature AVR micro-controller from
Atmel featuring 256K Flash, 8K RAM, 86 I/O lines, 16 ADCs, 4 UARTs, 6 Timers, 8 Inter-
rupts and much more.
All AVR micro-controllers can be programmed using ICSP, external programmer or boot-
loader. Advantage with the boot-loader is that you don’t need any external hardware
to load the .hex file on the micro-controller. If Boot-loader firmware is loaded on the
micro-controller then it can be programmed directly via serial port of USB using PC.
We have already loaded the boot-loader firmware on ATmega2560 micro-controller. It
is recommended that you always update the firmware on ATmega2560 either through
wired via Micro-USB port or wirelessly i.e. Over-The-Air (OTA). For more information
on how to update the firmware OTA, refer the Section Button - Wireless Flash in the
Software Manual of eYFi-Mega development board .
2.1.2 ESP32 micro-controller
ESP32-WROOM-32 is a powerful, generic Wi-Fi+BT+BLE MCU module that targets a
wide variety of applications, ranging from low-power sensor networks to the most de-
manding tasks, such as voice encoding, music streaming and MP3 decoding.
It has integrated SPI flash of 4 MB . We have partitioned this memory of on-board ESP32
to accommodate 1 MB OTA (Over-The-Air) application, 2 MB User application and 700
KB File Storage . This partition table can be modified by you as per your requirement.
For example, if you want to increase or decrease the size of the 700 KB File Storage
you can update the partition table. If you decide to modify the partition table for your
project, you might not be able to use the OTA App because our OTA App is compatible
with the partition table described below (Refer Table 3). In case you accidentally erase
the partition you can download our Partition Table and our OTA App from our website.
The current partition table is described below:
Table 3: Partition Table of on-board ESP32 micro-controller
Partition Name Start Address Size
reserved area (nvs, otadata, phy_init) – 300 KB
factory (ota-app) 0x10000 1 MB
app1 (user-app) 0x110000 2 MB
storage (spiffs) 0x310000 700 KB
2.1.3 16 MHz crystal
The frequency of crystal connected to ATmega2560 is 16 MHz .
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