#Sabretooth 2438, Ah, you need to read quite a lot before designing something. You might find some of the references in my answer to the following question useful: raspberrypi.stackexchange.com/questions/124791/…. Have a great stepper motor project. Cheers.

Now I assume you are trying to use NI Multisim to design a stepping motor driver to drive a bipolar stepping motor. You need to specify the input signals to the stepping motor driver. You might use A4988 microstepping motor driver as a example, though you might only need to implement full and half step mode. So for the A4988 case, the ms1. ms2, ms3 can be simplified to only to ms1 which configs full step if H, half step if L. Like this: i.imgur.com/eE3wueL.png.

@tlfong01 sorry, but how can I implement it in the sub PLD (Stepper Motor Driver) file, since the only components you have is mostly based on Boolean

I don't understand what do you mean by "since the only components you have is mostly based on Boolean"? Can you give me an example? Or perhaps I can give an example, say, a full adder. For a full adder, you specify the inputs and outputs, of course they are all Boolean, and NIM will implement the full adder for you, using logic gates (combinatorial and sequential components). Do I understand your situation and NIM's function correctly?

@tlfong01 I believe so, I apologize I am still a 2nd years student so my knowledge is still limited, and so far we have covered flip-flops so I am still a bit confused about this project but thank you for the help Edit: in the PLD will I be using the counter or flip flops if you don't mind

Ah, you remind me my long long ago years studying my rusty EE diploma. I learnt about logic gates and binary counters etc. I must confess that even after graduation I still have vague ideas about combinatory and sequential circuits, level and edge triggering, 555 monostable/astable/bistable stuff. I knew K-map very well, and drilled and drilled a lot, because they were favourite exam questions, :). Now coming back to your question. Are you sure your full/half step table is really a K-map? / to continue, ...

I still remember that K-Map is for combinatory stuff. For sequential things, you need something called a "state diagram". :) Any way, I need to read again the MicroChip/Iowa prof's good tutorial on stepping motor, to refresh my memory on the meaning of full/half/microstepping etc, and see if I can suggest a spec for your NIM project. Cheers.

This is the Iowa Uni Prof DW Jones' very good tutorial I read when learning the stuff: homepage.divms.uiowa.edu/~jones/step/an907a.pdf. Perhaps you can also read it and we can use it as a reference of terms when discussing the NIM project. Cheers.

Another good reference is this one: How to control unipolar/bipolar stepper/stepping motors such as ... , RpiSE 2019apr27, Viewed 887 times raspberrypi.stackexchange.com/questions/97975/…. These two references give the big picture of stepping motors. I usually recommend to first look at the big picture, ie, the woods (all about stepping motors), then the trees (our NIM project on bipolar stepping motor). Of course it is the trees that Stack Overflow suggest us to laser sharply focus.

@tlfong01 I am not sure about the k-map, I assumed there should one. All I am looking for is the procedures and how can I obtain the values to make the project work

Hello

@Sabretooth2438 I see. I agree there is some confusion about the full/half step "sequence". I found it interesting that no one seems interested to give a name to the sequence. If I was asked to give a title or name, I would say something like "Sequence of steps to power/signal to the two coils of the bipolar two coil four leads stepping motor. Of course this is too long winded.

let send you the full question that we received

Design a half-step sequence stepper motor driver digital circuit. Half-step sequence mode states (combination) causes step angle θ° of shaft rotation in stepper motor (step angle θ=0.9° ).

The three modes of operation are shown in Table 1. There are only four states in the full-step sequence and wave-drive sequence. On the other hand, there are eight states in the half-step sequence as shown in table 1. Figure 1 shows the stepper motor driver where it has two inputs and four outputs.

If D=0 the sequence will be the sequence in the table from row 1 to row 8 and If D=1 the sequence will be from row 8 to row 1. The second input is the clock input which controls the speed of operation.

If you would like to suggest a better name, or if you happen to find other tutorials using a better name, you might let me know and we would discuss to agree on a better name. I do think K-map is not very appropriate or a bit misleading.

this is for HAlf step

@tlfong01 the reason I said kmap because the whole semester we were dealing with truth table

so i assumed kmap will be associated with it

Ah, the question is good. So other names can be "motor coils drive sequence", "state diagram" etc. But that is not important. We can for name just use a casual name, say "Half step motor drive sequence" and you might like to propose a better name name later.

Another question. If you read Iowa Uni Prof Jones's tutorial, you might see him showing a schematic with something called full/half "H-bridge", usually implemented using NPN/PNP BJT or N/P -channel power MOISFET. A motor driver such as L293D already has this. Now if your NIM has this "H-bridge thing" is the library, then you can directly use it. Otherwise you need to use BJT/MOSFET to implement this H-bridge.

Sorry, I couldn't follow

Yes, default full step is 1.8 degrees, so half step is 0.9 degrees. This is pretty standard of stepping motors. You might find me using NEMA17 stepping motor which has .8 degree as the standard.

do we have that in multisim?

all I could find stepper motor phase

2 phase*

that is connected to the stepper motor driver

that I have to work on it

Ah, I am talking too fast. So you might like to skim the two references I gave you, focusing on "bipolar", "two coils", "two phase", "four leads/wires", "full/half step" etc. Then google/wiki "H-bridge", and perhaps also "L293D". I will wait for you for perhaps one or 2 days to catch up.

honestly compare to you I feel stupid.

You need to go slowly otherwise you won't learn thoroughly and remember things hard. Question: what is the dead line? :)

it is next month on 13

but we also have other assignments coming up

so I want to finish it as much as possible

Well, comparing to me, long long time ago, studying my rusty EE diploma, I think you are OK, at least as smart as me. :)

I wish, because of covid we have lack of practical that is why we are learning on Multisim

so most of the stuff I am not understanding well

but managing it barely

I see. So deadline is June 13. Another question: Is yours an individual project, or a group project, or is everybody giving the same assignment, and so you guys can discuss on line?

Ah, so it is Covid19's fault. Otherwise you can go to the practical lab, find a L293D and wired up the circuit with a motor, test it, then you can learn well.

Anyway, I think you need to learn the full/half bridge theory/operation, never mind BJT or MOSFET.

@tlfong01 individual, but we still discuss it in the group but so far now I am the only one who started

ok, I'll do that

Ha, so you are an early bird. Ah, I missed my locking down afternoon tea. So I will leave you to read the stuff. In the mean time, you are welcome to ask me newbie questions though. Cheers.

Now I am skimming the NIM user manual:

ni.com/pdf/manuals/374483d.pdf

Please confirm if you are reading the same 2009jan (seemingly a bit out of date) version.

So I skimmed the user manual and I am not impressed at all, because I don't find too many high level components in the components database. Below is my wish list:

1. Full H-bridge

2. DC Motor

DC Motor is not important, because you can use two resistors to fake the two coils of a bipolar stepping motor.

But the full H-bridge is crucial, because it is the core component of the stepping motor driver. Or can you ask your tutor if there is any H-bridge and ／　ｔｏ　ｃｏｎｔｉｎｕｅ，　．．．

he just gave us this Multisim schematic the one in the forum

all I have to do is create logic in the subPLD file

which is stepper motor drive

which I believe I have to implement the logic w learned this semster

forgot to mention my course called Digital Devices and Systems EN6020

so it is mostly based on logic gates and truth table and bolean expressions

So you only need to use counters, flip flops, to complete the exercise, no need to design H-bridge or DC motor? Then it should not be that hard.

yes

counters and flip flops are just only speculation

because I noticed how the logic worked in the table

Ha, then you should not worry that much.

for half step I am kinda confused a bit

in full step it is easy to fin the next step

but in the half step I didn't understand why it converted to 0 or 1

Ah, so you don't understand the half step thing. Perhaps you should read Prof Jones's tutorial very carefully.

ok

Ah, you have given me enough info now. You might like to show me the "schematic" in the forum, then I can have a clearer picture. But no hurry at all. Perhaps tomorrow or day after tomorrow. Ah bed time. Call it a day. See you tomorrow or later. Bye.

sure, still working on it

have a nice day and thank you for the help

You are welcome. Good luck. Cheers.