Three questions

Discussion in 'The Projects Forum' started by iPromise, Aug 12, 2013.

  1. iPromise

    Thread Starter New Member

    Aug 11, 2013
    Hey guys,

    I think I can say i've achieved a high degree of understanding with computer programming. I am now coding kernel drivers and other types of high-end software.

    But I would like to my skills to good use.

    I want to start learning about digital circuits so I am able to create my own circuits, and then put code in them. For instance, I want to eventually start off by creating my own clock, then calculator and so forth.

    I remember my computer engineering teacher telling me that towards the end of the six month course (in high school) they created logic gates from scratch and made a basic device for the game rock, paper scissors.

    I thought that was cool but I was curious as to how they managed to be able to grasp enough knowledge to create their own circuit from scratch and create a basic electronic device in just six months. I posted a few questions about transistors and logic gates and I was told that it takes many months, even years to be able to understand it to that degree.

    So my first question is what type of transistors can you think of that my teacher had his students create to assemble their own logic gates and how were they able to understand how to create that within a short duration?

    My second question is does this faculty (understanding and creating digital circuits on your own/in companies) all fall under electrical engineering?

    My final question is where do you write your computer code in the digital circuit you've assembled and how is it written? How does the circuit remember your code that you've written to it?
  2. LDC3

    Active Member

    Apr 27, 2013
    He probably was using BJT transistors and you can read a basic outline of them here. It will take about an hour or so. You would only need to understand how to use a transistor as a switch.

    I believe it does.

    Unless you used a microprocessor or a programmable gate array, the logic is hardwired into the circuit you constructed.
  3. #12


    Nov 30, 2010
    Dear Promise,

    I think you have a mistaken impression. Now, I'm going to say what LDC3 said, but in different words.

    1) Students do not make transistors. That requires a furnace and an ultra-clean laboratory. They just bought some transistors and spent a few weeks on theory. Then the teacher showed them how to connect parts, handed them the schematics, and watched to see who could follow instructions.

    2) The act of designing digital gates with transistors is actually engineering, but the High School students didn't do that. The teacher showed them drawings of standard designs and taught them how to connect several circuits together to make something besides a 1 and a 0.

    3) There is no way a High School student with a box of transistors is going to learn the theory and practical application of transistors, build a CPU, a kilobyte of RAM, an input reader, a compiler, and an output display in 6 months.

    It's a cute course, and it was serious geek cred in the 1950's, but programming is so far removed from physical assembly that you can learn 6 languages and never see a transistor.

    Love your enthusiasm, but the difference between coding kernel drivers and assembling discrete transistors resembles the difference between piloting an airplane and making a Gilligan's Island coconut telephone. It's nice to know how ones and zeros are made, but that is so many generations behind where you are that it is only a curiosity. Don't spend too much time on transistors. You are much more valuable piloting the CPU's.
    Last edited: Aug 13, 2013
  4. MrChips


    Oct 2, 2009
    Nice analogy.
    #12 likes this.
  5. crutschow


    Mar 14, 2008
    iPromise, I find it quite interesting that you have a high degree of programming skill but apparently never learned how a stored-program computer works. I always thought learning both rather went together but, in retrospect, I can see that they don't necessarily. ;)
  6. Shagas

    Active Member

    May 13, 2013
    Took me about a year to get my electronics to a 'decent' level where I could build fun and interesting/usefull projects (both analog and digital) by designing them myself out of intuition and not needing external schematics etc.
    Sure , i'm abit sloppy when it comes to calculation and accuracy but when you meet that hurdle you can always do some reading on the specific issue and go on.
    If you want to learn digital electronics then it will take you at least 2-3 months of 3-4 hours a day to get to the level where you sort of know what is going on and you have got a muddy picture of the whole realm . Then you will start cleaning up concepts and areas one by one. (in my opinion at least)