Final project - Hardware

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        Hardware  Architecture 
        Functional  Specifications
         Parts  list technical specification

HW Architecture


Wikipedia definition of HardWare Architecture

In engineering, Hardware Architecture refers to the identification of a system's physical components and their interrelationships.

Often called a hardware design model, allows hardware designers to understand how their components fits into a system architecture and provides to software component designerss important information needed for software development and integration.

its is a representation because it is used to convey information about the related elements comprising a hrdware system, the relationships among these elements, and the rules governing the relationships.

It is a process because a sequence of steps is prescribed to produce or change architecture, and/or a design from that architecture, or a hardware system within a set os constrains.

It is a discipline because a body of knowledge is used to inform practitioners as to the most effective way to design the system within a set of constraints.


Continue reading a good book here: Chapter 1. An Introduction to Computer Architecture

Raspberry

Image from Element 14 GOOD documentation

Hardware Specifications


Pi Camera NoIR MIPI CSI-2 Interface

Audio Output 3.5mm jack - is a electrical connector tipically used for analog audio signals.

I need to understand the audio jacks and found a nice documentation here: CUI INC...

Modularity

As professor Neil defends, we should design modular systems since they are easier to debug and enhance the life of the whole system by enaibling the possibility to change damaged modules, instead of the whole system...


So I thought on organizing the HW system according to the functionalities associated to each other, so we have the following Modules:

  1. Temperature and Humidity:

  2. Carbon dioxide and Ventilation:

  3. Image and Sound:

HW design

connecting the modules, being the last two mo

Module 1 - Temperature and Humidity, I will need to have on the board:


  1. Attiny44
  2. DHT11 - 4 pins/PAD's?????
  3. 10K resistor connected to DHT11 data pin and Microcontroller VCC - note online
  4. Grove - Water Atomization V.01 - 2 pins
  5. Heating Pad's -
  6. 2 MOSFET, N Channel, 30V, 1.7A, 500mW, SOT-23
  7. i2C pins

considerations when designing the board in eagle:

finally on Eagle made this board

Download Eagle Schematic
Download Eagle Schematic

Module 2 - Carbon dioxide and Ventilation, I will need to have on the board:

  1. Attiny44
  2. Co2 - 4 pins
  3. Fan - 2 pins
  4. i2C pins
  5. need to figure out how to handle two i2C connections in this board

Figuring out how to handle i2C in attiny44 so that it behaves as Raspberry slave and as Co2 board Master...

When looking for experiences online and found quite a few...

The question is that to do i2C in a Attiny44 we need to use:

So looked online for situations where Attiny44 has two i2c busses, one as Slave and other as Slave

AVR Freaks... ATTiny with both I2C Slave and I2C Master separate buses - Use HW I2C for the slave since a software slave is difficult.Use any other 2 pins to implement software master.

Now this one is quite practical...

Arduino Forum... 2 I2C buses on an ATtiny85 (Read 154 times)... "I2C protocol can be implemented on any 2 GPIO pins. It's easier to simulate a master versus a slave, but they're both possible. There are plenty of "bit-bang" libraries which can do this for you (like mine)".

... it seams that there is also a Library to implement i2cBiy-Bang on any AVR...

bitbank2/BitBang_I2C 
        ... The purpose of this code is to provide a simple C library which can bit-bang the I2C protocol on any 2 GPIO pins on any system. The I2C protocol doesn't require any special functionality of the pins beyond standard GPIO features....

Module 3 - MAIN as Master, and connecting to Camera and Speakers:

  1. Raspberry Pi 3
  2. Raspberry pi Camera Noir
  3. Speakers
  4. i2C Wires
  5. IR led... would be important if want to use NoIR filter of this camera

Power Consuption


Part Voltage Current
Heating Pad 5V 0,74 A
Misty Maker 5V 0,4 A
DHT11 5V 0,3 mA
Co2 5V
Fan 5V 0,26 V
Total ~1,4
Raspberry Pi 3 2 output pins of 5V 1,5 A

Hardware Specifications

Sensor Incubation value reference frutification value reference Part reference
Humidity 80% humidity or more 80%-85%
Temperature 23º - 25º 18º
Moisture since moisture = soil (temperature & humidity) the value references are the same as above xxxxx
pH Mycelium: 7 (or 6) Fuiting: 7-8
Image detect dimensions detect colors
CO2 mushroom spaw - 10 000 ppm to 20 000ppm mushroom grow - 800 ppm to 1 500 ppm new mycelium begins grow >= 5 000 ppm


Actuator Function Value refences Part reference
Air Flow circulate air inside/outside 80%-85%
Air Filter control organismes and particles HEPA
Camera take photos Computer vision SW to analise evolution/state of the living fungui Raspberry Pi NoIR Camera V2
IR led move Computer Vision set (camera & IR led) to new positions - survilance of Fungui
Motor (Computer vision set movement) move to new positions - monitor Fungui should shot light for NoIR photos... not always!?
Sound Sound waves (music or other frequencies)
- frequencies of 0.1 kHz to 1 kHz and intensity of 70 dB to 80dB		 attention to sound wave propagation - materials for walls SPEAKER MINIATURE 2.5" 8OHM - Speaker, Mini, 60 mm, 0.5 W, 8 ohm, 260 Hz to 4 kHz
Temperature Heat or Refresh the environment Could be made out of a 3D printer heating BED
Humidity enhance the quantity of water in interior air or substract a few water drops over time or Mist machine


Parts list and characterization


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