EEVblog #1249 - TUTORIAL: Timing Diagrams Explained

A tutorial on how to read timing diagrams. An essential skill for designing and understanding digital logic, FPGA and microcontroller designs and datasheets.

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[Mtaalas]

Once again a topic that I would have killed for when I was a student :)
Keep them coming, you're doing an amazing job. EE is still something there's very little real teaching material online that's RELIABLE and coming from a real EE :)

[shifter]

Love the distilled knowledge in this video. Years of experience summed up in less than an hour.

[Radiofreak]

9:11 That's called a zero se-tup time, so that means that there's zero set-up time. Thanks Dave! ;)

[JakobWierzbowski]

Thanks Dave, you had the right timing :D for this video

[Schwuuuuup]

did anyone notice how many of Daves (fundamentals) videos start with a (lengthy) justification, why something should be understood? It's like the target group of those videos is a guy who just said "Nah, I don't read datasheets.... I just put some wires together and if it doesn't work, I'll call it a piece of crap.... Timing diagrams are just show off for fancy people"

[jamisonw.]

Dave, you should give Shenzen IO a try. It'd be funny to do a "let's play" but it actually has some quality engineering concepts to go through. I mention it here because the goal of the game is to match a data output signal using different chips and assembly language.

[idkEngineering]

This is the kind of content that got me into your channel when I was back in high school! Great to see it more of it!

[tomservo]

perfect timing (no pun intended), I was looking for tutorials. Thanks Dave!

[jon]

I was just developing some timing diagrams, too! This is perfect

[CaspaB]

I don't believe in frequencies above my audio threshold ( DC to 12 kHz ) so reading timing diagrams is easier. ;-)
I'm stuck in the 1980's (CMOS, TTL) era

[IsaacMorton]

Very helpful! I've kinda just been guessing my way through those up till now. Very informative!!

[crazyboycashier]

I’m working on a z80 and have got quite far into it but this makes more sense

[markpitt]

This is a great explanation, timing is a simple concept but when implemented gets complex very quickly. Its a case of seeing the wood for the trees, I look at some datasheet timing diagrams and my mind just panics! Knowing the very basics mean you can break it down into chunks and find the stuff that is relevant to you and what you want to achieve with a circuit.

[dogastus]

This could do with a Part 2 describing pipelined logic comparing, say, hold time outputs of registers to setup times of succeeding registers. It's easy to violate these timings especially if you have long PCB traces. A trap is to feed high speed logic into low speed like a 74F logic feeding 74LS logic. Also, how to deal with meta-stability issues in asynchronous systems.

[rhama]

An excellent fundamentals video, thank you.

[twjonckheere]

I still remember the first time I discovered timing diagrams when working with SPI communication between an Arduino and a digital potentiometer. I bought a logic analyzer to study the timings and worked through getting it to work. One of my top moments in learning electronics for sure.

[TimeWasted]

This is a perfect video. So much good information. Thank you!

[leoramikam]

Can you please help me with this diagram?

digitalWrite(PIN_CS, 0);
delay(1);
digitalWrite(PIN_WRITE, 0);
delay(1);
digitalWrite(PIN_B0, 0);
digitalWrite(PIN_B1, 1);
digitalWrite(PIN_B2, 0);
digitalWrite(PIN_B3, 1);
digitalWrite(PIN_B4, 0);
digitalWrite(PIN_B5, 0);
digitalWrite(PIN_B6, 0);
digitalWrite(PIN_B7, 0);
digitalWrite(PIN_WRITE, 1);
delay(1);
digitalWrite(PIN_CS, 1);

[kevincozens]

Good tutorial as always, Dave. I've been reading timing diagrams for decades. Timing diagrams for microprocessors are fun to look with how they are marked up. They can look quite intimidating to the newbie. Always interesting deciphering address and data bus set up and hold times.

[worroSfOretsevraH]

A nice follow up would be an introduction to reading through a more complex digital circuit made out of logic elements. For ex. a full adder or even something that has flip-flops mixed in.