Microcomputers Topics

#1

A microcomputer is a small, relatively inexpensive computers with a microprocessor as its processing unit, general purpose input and output (GPIO) among other peripherals. The ARM A series microprocessors caused a revolution in the world of smartphones and computing. In this forum we will concentrate on how the computing world was change by this revolution. In this era, microcumputers are credit card sized computers with CPU speeds of upto GHz and more. Some of the microcomputers in the market are;

  1. RaspberryPi
  2. Beagle Bone
  3. Banana Pi
  4. Odroid.
    Among others.

In this forum we shall explore this credit sized computers and get to tinker with some of them.

#2

On this forum we will start with the Raspberry Pi, because, one its available locally at affordable prices and secondly it has a large community and well it’s like the arduino of single board computers.

So how did raspberry pi come to be?

Raspberry Pi was created in February 2012 by the Raspberry Pi Foundation in UK. The Pi (will use this to refer to the raspberry pi) was designed for the purpose of teaching computing skills to students in schools and colleges around UK. However, Pi fell into hands of “Tech-heads” who immediately fell in love with the credit size computer and by February 2014 the Raspberry Pi Foundation had sold 4.5 million boards, and as they say the rest is history.

The Raspberry Pi have various models of the Pi which are;

  1. Raspberry Pi 1 A/ A+
    2 Raspberry Pi 2 B/B+
  2. Raspberry Pi 3 B
  3. Raspberry Pi Zero

The Raspberry Pi Zero been the most recent and going for just 5 USD (500 Ksh), I got one from here

Raspberry Pi 3 model B was also released recently with added WiFi and Bluetooth capabilities.

Raspberry Pi run on popular light weight linux Debian, the Pi foundation has created an OS image called Raspbian, which is copied to an SD card and the Pi boots from there, we shall discuss how to install Raspbian later.

What can you do with a Pi?

Raspberry Pi has a lot of processing power and with this we can do a lot of cool stuff e.g
Image Processing
Build a smart Home monitor.
Have the pi tweet for you among others.

In this Forum we shall start from the basics e.g have pi tweet for you the room temperatures and advance to other complex topics such as machine learning.

If you want to learn more about Pi you can visit the Raspberry Pi official site.

#3

Hello guys,

I would like have a collaborative design exercise to design a raspberry Pi Hat or pHat (Hardware Attached on-Top), this is an equivalent to designing a shield for an Arduino, only in this case it’s for a raspberry pi.
I have some ideas in mind but would like to have more ideas from you and we settle for the best and most viable. My ideas are:
1. A weather Hat ( a hat that can have sensors such as humidity, temperature etc)
2. A pi Radio Hat ( Have a hat that can stream internet radio)

Am looking forward to have many more ideas from you.

#4

Can we prototype a linux-based board?
We can pick the design and inspiration from the pi.

#5

Here is the link:
https://www.raspberrypi.org/documentation/hardware/raspberrypi/schematics/README.md

#6

How about starting with the simplest of the two then taking up a more challenging project once participation increases? i.e. starting with a Pi HAT then growing into a board? How many layers is the Pi PCB? IF simple enough, why not.

It would be interesting to do a smart home system with nanny cam given the increased demand and possible commercialization interest for this.

More ideas welcomed.

#7

The Raspberry Pi is 6 layers, so designing a linux board would be quite an uphill task, I would rather we start with a Pi HAT then proceed to a board. A smart home system is a brilliant idea @AYSande , we can brainstorm here n the forum what sensors we would have in such a system.

What do you think guys?

#8

Great idea, couldn’t agree anymore.

So we do the HAT(s) required for the smart home first?

#9

Yeah that’s the idea @denzel , could you be having ideas in mind of what sensors we could incorporate in a smart home?

#10
  • Temperature
  • Humidity
  • Air Quality
  • Smoke Detector
#11

Awesome @denzel , that’s great. I have previously left my taps open when there wasn’t water in the morning, only to find my house flooded i the evening :scream::scream::scream::cry: ( well might call it careless but it has happened to most of us :smirk:) How do we go about that?

It wouldn’t be a smart home if nothing got done, so we can add MOSFET of relays to switch off the lights, switch off all other non-essential sockets when you not in the room.

What do you think?

#12

Great ideas.

Would it be an overkill to add a nanny cam, perhaps with capacity to listen in as well? With this, we could create a business case for every modern home to have a Raspberry Pi with the home TV as a dashboard.

Also, would it be possible to reuse the same Pi as a Home Theatre PC (HTPC) and for kids to learn programming, play games…?

#13

It wouldn’t be an overkill if the nanny cam was just streaming Video and audio, and yes the same pi can be used as a learning and entertainment hub for the kids Awesome idea @AYSande :+1:.

#14

At the risk of over-crowding our piHAT we could also add an LPG sensor and motion detector. An ambient light sensor could also be useful. And it’s really tiny anyway.

#15

Hmm… I can not help but join this forum.

Going by the trend of discussions here, it seems we are working on a smart home, implementing a Pi. cyrus, is that so? What are the objectives to constrain our scope in this particular forum please?

For the problem of water, i suggest we can have a motion detector such as PIR (Has excellent range and detection angle) as occupancy detector to monitor activities within a room, and a solenoid valve at the tap pipe to choke the water if no activity is observed in the room for more than 1Hour or so.

the motion sensors can also be linked to lighting such that when there is no motion, lights go off in a room (relay actuators). we can also have some special sockets connected to this system, so that they can hold appliances such as TV, room heaters, computers, DVD players, Home theatres, and such gadgets that need someone to be present when in operation, and can be easily left ON and silently draw alot of power unnecessarily. This system can be handy in auto switching them off when no one is inhouse, Saving alot of electrical and water bills

we may have also some bluetooth module to interface the system to link with a smartphone app that can be used as the user interface for display and control.

of course the links between all the smart sensors and actuators can be wireless if distances are long. we can think of low cost RF modules that can implement networking eg NRF24L01

SUMMARY
SENSORS

  • Temperature sensor & smoke detector (Fire detection)
  • PIR (Room Occupancy detection)
    -Nanny cam (Videos and pictures)
  • more?

ACTUATORS

  • Relays (for sockets, lamps)
  • Solenoid valve (For water pipes)
    -more?

COMMUNICATION
-Bluetooth modlule ( System to custom phone app for user interface)
-RF modules (Mesh networking between sensors, actuators and the Data acquisition point)
-WIFI module (streaming nanny cam videos and pictures over internet)

#16

Hello Guys, sorry have been away for a while. Great ideas fro yo, really appreciate. Welcome aboard @Michael , thank you for shortlisting some of the sensors and actuators we would need.
To add on your list, we could add LPG gas sensors (MQ6 ) this would serve as a preventive measure before a fire occurs due to a gas leak. NRF2401 is a great communication tool and fairly cheap, so i agree on you on that.

As for the for phone application and the bluetooth capabilities, the Raspberry Pi 3 comes with bluetooth and wifi, so it would save us much footprint not to include a bluetooth radio on our PHAT, that is in assumption that the users will be using a PI 3.

A while back i was designing an automated sprinkler system for homes with lawns and was using the NRF2401 radio module, i would like to rekindle that project and have it as part of the automation will be having with this PHAT.

#17

Good summary @Michael

Could we look to have it mounted near or at the TV area so that the Pi can also be used as a home PC and Home Theater TV?

#18

Hmm… That could be a nice idea. I have been thinking about the current smart TVs common today that can connect to the internet and do most things the normal PC can do. we may need to come up with an interesting feature in addition to Home PC function that may add more value for use with a smart TV

I have worked a little bit with the PI B+, it is quite a good gadget, though for a RAM of 512Mbs or 1GB, and clock speed of about 900MHz may not be so much capable of handling tasking work. we may put this to the constrains as we design our system

#19

Cool @Michael, the raspberry Pi 3 has a higher clock speed of 1.2Ghz thou with a RAM memory of 1GB also, has a great tonne of power for a single board computer.

As for the Home theater TV, we can try out Kodi which is an opensource and free software media center that can run on linux. Further more, there is a raspberry pi distribute of the same called OSMC We can try this out on a raspberry pi without the HAT, then after Proof of concept we can design the inclusion of audio output on the HAT for better experience. You an read on how to install OSMC Here

@Michael since you have a Pi 2 B+, you can run the OSMC on it and I will run it on Pi 3, and I think @denzel too, then we can give feedback on the performance of the two here.

#20

Download OSMC from Here, it’s a disc image, so will have to write on a New SD card other than the one you have installed the raspbian OS. Or alternatively, you can install it to a the Pi manually (will run in the raspbian OS), just follow these instructions