Question about Hall switches that I am planning to use as limit switches.

@zander I haven't seen anything about special macros. Can you point me to something about them? 

@pritchs Are you sure you don't have a Blue Tooth or WiFi capability? I can control almost everything on my Canon 7DII plus pan and rotate from over 100 yds away.

@pritchs I am on the spectrum so lousy memory but I will try. What board are you using, esp8266 or esp32?

@zander Some of the VIXIA models do have Canon Connect I see, but ours are fairly old. I would have to get the specific model and look it up. If they do, however, you could have made some serious money betting with me that they had anything like that. 😀 We've never had a reason to use it though since we use live camera operators.

Even if they do have that capability, I think I would rather put it "all in one box" rather than have to have a phone as well as a control box. The folks that may be running this thing tend to be quite a ways to the left side on the technology bell curve. Nice folks. Just not technically oriented. And the reason I was looking for reliable limit switches. 

If you remember about the macros, great. If not, no worries. I'm 75 going on 76 and I understand about memory issues!

Cheers,

sp

@zander Oops, forgot. I'm using an Expressiff ESP32 board with WIFI. I'm planning on using ESPNOW to communicate. Seems to work well over the short distances we'll be using.

@pritchs Ok youngster, I didn't find what I was looking for but did find this. I strongly recommend that you do NOT use interrupts, all you need is a readDigital at the top of your loop, you don't have any real time critical things happening so an interrupt just introduces unneeded complexity. This is a bad example but shows the IRAM macro. All an ISR should do is set a flag that is handled in the main loop in exactly the same place as the digitalRead. If you come back with an Interrupt question I will give you such a hard time.

https://microcontrollerslab.com/esp32-external-interrupts-tutorial-arduino-ide/

@pritchs I know some Canon DSLR and probably others have built in remote but I actually use a 3rd party so a dongle hangs off my camera plugged into the USB port. If it ever transpires that you wish you had remote control over the camera, just send me a DM if you need any help looking into it. Like I said earlier, cameras and computers for over 50 yrs so i generally have good hunches.

@zander Thanks for the info on the remote control for the video camera. I will definitely keep it in mind. If we were to have to pick on of the axis to use, zoom would probably be the one we would pick. So if this contraption doesn't work out, I'll give you a shout.

I went looking for macros and interrupts and there is some information, but, and I've only skimmed through a couple, it seems that the attachInterrupt function does some things for one that one would have to do without it. Setting interrupts up manually results in faster execution, whereas taking the easy road is a little slower. Definitely not the first time that's been the case with computers - and many things in life. Like I said, that's from a quick scan and my not hold up under a careful read. 

I'm not promising I won't ask an interrupt question, but I'll try not to. 🙂

Thanks for the help.

SP

@pritchs Keep in mind that faster in this case is a few millionths of a second vs a few millionths of a second plus a few more millionths. Your finished code will look almost identical, check a ISR set variable for an interrupt to process, vs check a digital pin for some input to process. The time difference is basically the time it takes to execute a digitalRead minus the ISR service time. Yes it's faster, but you can't observe it. BUT when you don't enable/disable interrupts in the right place and lose one as a result you will notice the difference. With the digital read it will be there when you get around to that statement next loop pass. Good luck.

Posted by: @pritchs

↑

@inst-tech Thanks for the info. It helps a lot to get advice from people like you and others here that have been in a particular specialty and have real-life experience.

From this discussion, I'm going to try photosensors. They seem to be the least trouble. But then again, that's why I went the Hall switch route. 😀 The limit switches are the last major hurdle I know about, so it ought to go relatively quickly from this point. But who hasn't thought THAT before? 

Thanks again.

SP

@@pritchs,  Yep..I have always ascribed to the K.I.S.S. method.."The limit switches are the last major hurdle I know about, so it ought to go relatively quickly from this point. But who hasn't thought THAT before?"  indeed..and we have all done just that !... That's why we always said in the business, "There's nothing I can really do in less than an hour! LOL....  You just never know what your going to get into until you actually start.. then all the little gremlins come out to play, reeking havoc on your "well thought out project"...

One thing is for sure, that's half the fun of building something, and the other half is the satisfaction of it actually working!..

Be safe, and have fun..

regards,

LouisR 

@inst-tech Along those same lines in woodturning we say, "Never take that last cut." Why? Because that's always the cut when you go through the side or the bottom or have a big catch, all of which destroy the piece. Once one is proficient, that doesn't happen too much, but it is always there waiting for you to misjudge the depth of cut or thickness of the material. It is often tempting to make just one more cut to get some minor imperfection out that would probably sand out, only to misjudge something and have a complete failure. It must be said that at least failures on the lathe are normally pretty spectacular. Some great stories come out of those failures. :-0

Regards,

SP

@pritchs

Posted by: @pritchs

↑

@inst-tech Along those same lines in woodturning we say, "Never take that last cut." Why? Because that's always the cut when you go through the side or the bottom or have a big catch, all of which destroy the piece. Once one is proficient, that doesn't happen too much, but it is always there waiting for you to misjudge the depth of cut or thickness of the material. It is often tempting to make just one more cut to get some minor imperfection out that would probably sand out, only to misjudge something and have a complete failure. It must be said that at least failures on the lathe are normally pretty spectacular. Some great stories come out of those failures. :-0

Regards,

SP

As someone in the engineering game building many automated machines, I recommend proximity sensors,  

https://www.ebay.com.au/sch/i.html?_from=R40&_trksid=p2380057.m570.l1311&_nkw=proximity+switch&_sacat=0

Posted by: @frogandtoad

↑

@pritchs

Posted by: @pritchs

↑

@inst-tech Along those same lines in woodturning we say, "Never take that last cut." Why? Because that's always the cut when you go through the side or the bottom or have a big catch, all of which destroy the piece. Once one is proficient, that doesn't happen too much, but it is always there waiting for you to misjudge the depth of cut or thickness of the material. It is often tempting to make just one more cut to get some minor imperfection out that would probably sand out, only to misjudge something and have a complete failure. It must be said that at least failures on the lathe are normally pretty spectacular. Some great stories come out of those failures. :-0

Regards,

SP

As someone in the engineering game building many automated machines, I recommend proximity sensors,  

https://www.ebay.com.au/sch/i.html?_from=R40&_trksid=p2380057.m570.l1311&_nkw=proximity+switch&_sacat=0

 

@frogandtoad, @pritchs

Indeed frogandtoad..I agree, as I too have alot of experience with machine automation..about 40 years worth...lol

The problem is that there are many different types of proximity sensors, with their advantages and disadvantages.  I've included a link for @pritchs, https://www.linquip.com/blog/types-of-proximity-sensors/ that describes those in detail..this may help him to decide which way he would like to go..

Regards,

LouisR

@inst-tech and frogandtoad, thanks for the suggestions. The article on proximity sensors was very helpful. 

SP

@inst-tech et al 

An interesting post that got me thinking about these components as switches. Your link shows that there are quite a range of contactless switches svailable, so I suppose my query is general to all of these, although specifically to the cheap Hall effect switches readily available.

My query is this: do these switches suffer from 'bounce'? That is  do the need to be denounced when integrated into a mcu design?

Just wondering....

Regards

Ron B