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1.3 Hardware used during experimentation and design concepts

Raspberry Pi B+ – A robust and powerful microcomputer
Specifications: Broadcom BCM2835 SoC processor with 700MHz ARM1176JZF-S core, 512MB RAM,
Videocore 4 GPU supports up to 1920×1200 resolution, microSD card slot, 10/100Mbps Ethernet
port, 4 x USB 2.0 ports, HDMI, audio/video jack, GPIO header, microUSB power port, DSI and CSI
Nano V3.0 – An inexpensive microcontroller
Specifications: Atmel ATmega328, Operating Voltage (logic level) 5 V, Input Voltage 7-12 V, Digital
I/O Pins-14 (of which 6 provide PWM output), Analogue Input Pins – 8,
DC Current per I/O Pin – 40 mA, Flash Memory – 32 KB, SRAM – 2 KB, EEPROM – 1 KB,
Clock Speed – 16 MHz
ESP8266 (Models ESP-01, ESP-12) – Wireless Module with System on Chip (SoC)
Specifications: 802.11 b/g/n protocol, Wi-Fi Direct (P2P), soft-AP, Integrated TCP/IP protocol stack,
Integrated TR switch, balun, LNA, Integrated PLL, regulators and power management units,
+19.5dBm output power in 802.11b mode, Integrated temperature sensor, Supports antenna
diversity, Power down leakage current of < 10uA, Integrated low power 32-bit CPU could be used
as application processor, SDIO 2.0, SPI, UART, STBC, 1×1 MIMO, 2×1 MIMO, A-MPDU & A-MSDU
aggregation & 0.4s guard interval, Wake up and transmit packets in < 2ms, Standby power
consumption of < 1.0mW (DTIM3)
DHT 22 – Temperature / Humidity Sensor
Specifications: Power supply: 3.3-6V DC, Output signal: digital signal via single-bus,
Sensing element: Polymer capacitor, Operating range: humidity 0-100%RH; temperature -40~80
Celsius, Accuracy: humidity +-2%RH(Max +-5%RH); temperature <+-0.5Celsius, Resolution or
sensitivity: humidity 0.1%RH; temperature 0.1Celsius, Repeatability humidity +-1%RH; temperature
+-0.2Celsius, Humidity hysteresis +-0.3%RH,
Long-term Stability +-0.5%RH/year, Sensing period Average: 2s
Opto-Relay Module – 5v Operating Voltage, Switching 250v AC @ 10A
1602 LCD Module + I2C Interface
Various push button switches, resistors, LED’s, Breadboard.


Author: Brian Lawes

A lover of how things work. Currently diving deep into the world of ServiceNow. Implementing Security Incident Response, Vulnerability Response, Threat Intelligence and developing cutting edge SecOps integrations. BEng(Hons) Computer Security & Forensics degree at Edinburgh Napier University. A Marine Mechanic to trade, also specialised in electrical/mechanical repair & maintenance.

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