MYP Design Hardware and Software Notes

Hardware Comes in Four Jobs, Not Four Shapes

1. Hardware is the physical parts you could drop on your foot, and every single piece is doing one of four jobs.
2. Input devices turn something in the world into data: a keyboard, a mouse, a graphics tablet, a 3D scanner, a microphone, a soil moisture probe.
3. Output devices turn data back into something a person can see, hear or hold: a monitor, a speaker, a 3D printer, a laser cutter, a vibration motor.
4. Storage devices keep data when the power is off: a solid state drive, a hard disk, an SD card, a USB stick.
5. Processing devices do the actual work on the data: the CPU for general instructions, and a GPU for anything with a lot of pixels or polygons.
6. One gadget can hold two jobs at once, which is why a touchscreen counts as an input device and an output device stacked on top of each other.

CPU, RAM and Storage: Three Different Kinds of Fast

1. The CPU, or central processing unit, carries out instructions billions of times a second, and splits into cores that can each work on a different task.
2. RAM, random access memory, is the desk: fast to reach, small, and wiped the instant the power goes.
3. Storage is the filing cabinet: slow by comparison, hundreds of times bigger, and it keeps everything with the power off.
4. Open a 400 MB CAD assembly and the machine copies it from storage into RAM, then the CPU works on the RAM copy, not the file.
   1. Run out of RAM and the computer starts shuffling parts of that model back to storage, which is why an 8 GB laptop crawls once the assembly gets big.
5. More cores speed up rendering and simulation, more RAM lets you keep more things open at once, so the two upgrades fix completely different complaints.

The Operating System Is the Layer You Never Chose

1. The operating system manages the hardware for everything else on the machine: Windows, macOS, Linux, Android, iOS.
2. It hands out CPU time, remembers which file lives where and draws the windows, so the people writing apps do not have to solve those problems again.
3. Application software is what you open to do a job: Fusion 360, Tinkercad, Inkscape, Figma, a spreadsheet, a browser.
4. Utility software sits between the two doing housekeeping: file compression, backups, antivirus scans, formatting a drive.
5. A driver is a small piece of software that teaches the operating system how to speak to one particular device, such as your studio's specific 3D printer.
6. A file that opens on one machine and not another is nearly always an application problem, which is why file formats like .svg, .stl and .pdf matter more to you than the brand of computer.

Embedded Systems: Computers That Do Not Look Like Computers

1. Most of the computers you own are not laptops: they are in the washing machine, the microwave, the car key, the bike light and the traffic light on the corner.
2. Each of those has one fixed job, a tiny amount of memory, usually no proper screen, and software written into the chip at the factory.
3. A microcontroller such as an Arduino Uno or a Raspberry Pi Pico is an embedded computer you are allowed to program yourself, which is why so many design projects sit on one.
   1. The Uno has 2 KB of RAM, about a millionth of what a mid range laptop carries, so sloppy code runs out of room fast.
4. Firmware is the software stored permanently on that chip, and updating it is deliberately harder than updating a phone app because a failed update can kill the whole product.
5. If your product must sense something and respond without a person watching, an embedded microcontroller beats a full computer on cost, size and power draw.

Open Source or Proprietary: Who Is Allowed to Change It

1. Proprietary software ships as a finished product: the source code stays with the company, and a licence agreement sets out what you may do with it.
2. Open source software publishes its source code under a licence that lets anyone read it, change it and pass the changed version on.
3. Blender, Inkscape, FreeCAD, KiCad and the Arduino development environment are all open source, and all of them are used professionally.
4. Open source is not the same as free of charge, and free of charge is not the same as open source: a browser based CAD tool can cost nothing and still keep its code locked.
5. Open tools suit school projects because they install at home with no licence key, so your work does not stop when the studio does.
6. Proprietary tools often win on polish, on support and on matching the file formats a manufacturer expects, which is a fair reason to choose them.

Choosing the Kit Before You Choose the Idea Is Backwards

1. Write down what the product must do first, then pick hardware and software that can conduct it.
2. Check the whole chain before you commit: a design is not makeable if the cutter wants .dxf and your drawing program only exports .ai.
3. Budget the dull parts too, because a missing SD card, power supply or USB cable will stop a build just as dead as a missing motor.

Testing Whether Your Choice Was Right

1. Try one small test piece on the real machine before you cut the real thing, because that is cheaper than finding out on your final panel.
2. Ask whether a user without your account, your licence and your laptop could still run the product you made.
3. In Evaluating, judge the tools as part of the outcome: a good product made in software nobody else can open is only half a success.