Dear Sparkfun,
I am trying to figure out why there is an interrupt on this device. Don’ get me wrong. I tested it with your examples and the interrupt works. But why have it. Does it work independently somehow and I haven’t figured it out?. I still have to read a pin to see if it was triggered, so why not just read the proxValue and decide what to do from that information?
Like any interrupt, it gives you the ability to focus on other tasks without having to constantly poll the device which is a waste of processor time and power.
Think about a battery powered application like a paper towel dispenser where you want to maximize battery life. The interrupt pin can be used to wake a sleeping microcontroller or to trigger a one-shot timer circuit that controls the amount of paper being dispensed.
The possibilities are nearly endless!
-Bill
Yes, if you have multiple micro controllers networked and so on. If you only have one, then polling is a chore on its to do list and you need to supply the SCL and SDA lines which involving more processing in the back round. I realize this sounds like I am complaining. I’m not. Sorry about that. I should start over.
I have tried various sensors, optical and otherwise, to detect a basketball scoring a basket. There are many examples out there, some more reliable than others. Polling seams to always be an issue, and an occasional basketball can slip by undetected. I am also using vibration sensors on the backboard detecting rebounds. The vibration sensors short to ground and first set an SR Latch. I never miss when sensing a rebound. I would like to use an SR latch for the score sensor as well. This way the basketball will never slip by undetected. The question I am really trying to answer is: What sensing device should I use that can be independent of the microcontroller?
Is there any reason why you can't use an external interrupt on your microcontroller? With the exception of very low-end 8-bit parts, almost all MCUs have them, Arduinos included.LEDLIT1:
Polling seams to always be an issue, and an occasional basketball can slip by undetected.
-Bill
No, there is no reason I can’t use an interrupt on my Arduino Nano other than re-configuring my hardware and rethinking and rewriting my code and testing and debugging and retesting and more debugging. It is a compromise, but I am willing to do all that. I really am. Maybe I should just do that. There problem is me. My mind is hung up. It believes there’s something out there out there that I simply can power up and it would give me a simple high or low when a basketball passes through a hoop. Sensing a basketball passing through a hoop has been around for a long time and there are thousands of machines already doing that. I guess I’ll just use the interrupt and see where that leads me.
On another note, I am having this reoccurring anomaly. If I load the sketch while the VCNL4040 is connected to my Nano I get this error: avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xe5.
When I unplug VCNL4040 The sketch loads and the sensor works. I’ve done this a few times while testing examples. It’s weird, right?. Then I realized I had plugged the VCNL4040 into the 5v supply. I tried it back in the 3.3v, but no good. Oh well. I guess i smoked it. I want to connect the other one I purchased, but I should probably take a break. It’s probably too delicate for a basketball hoop anyway. I just want to get back to developing this new game system and not worry whether the ball is detected accurately. I have audio to record and edit for the WAV trigger and custom animations to chart and program for the scoreboard and clock. I have to get back to writing and testing the games for the system. I just can’t seem to get a reliable detection of the basketball passing through the hoop. 999 out of 1000 seems like it should be easy. It shouldn’t be this difficult because its already been done.
Hi LEDLIT1.
I think we’re getting a bit off track here.
No, there is no reason I can’t use an interrupt on my Arduino Nano other than re-configuring my hardware and rethinking and rewriting my code and testing and debugging and retesting and more debugging. It is a compromise, but I am willing to do all that. I really am. Maybe I should just do that.
Using an interrupt on your micro controller would be the easiest, most reliable and best solution for your problem here. There are other ways to do this, but those involve additional hardware and testing anyway. An interrupt just works as long as you code for it, and interrupts are used for the specific problem you’re trying to solve.
On another note, I am having this reoccurring anomaly. If I load the sketch while the VCNL4040 is connected to my Nano I get this error: avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xe5.
When I unplug VCNL4040 The sketch loads and the sensor works.
Unfortunately I have no idea what would be causing this. The sensor itself doesn’t interfere with uploading code at all and the IDE and your Nano shouldn’t care if it’s connected or not.
I just can’t seem to get a reliable detection of the basketball passing through the hoop. 999 out of 1000 seems like it should be easy. It shouldn’t be this difficult because its already been done.
Sadly we don’t carry a sensor made specifically to sense a ball going through a hoop and I’m not familiar with the methods used to do that. You might want to contact someone that has a working system and see how they are doing it, otherwise it’s going to be trial and error until you figure out what works best. Figuring out what already works is going to save you a lot of time and effort.
Thank you for your time and support.
I just realized I am connecting the vcnl4040 interrupt to D2 on my Arduino Nano pinMode INPUT_PULLUP which is what 5v and the vcnl4040 is 3.3v . Did that damage the active low output of the vcnl4040? I smoked the first two I purchased because of input voltage was hooked to 5v. I purchased 2 more arriving Thursday and don’t want to smoke the new ones. Will D2 on the Nano damage the vcnl4040?
As long as D2 is setup as an input, you don’t need to worry about it damaging the sensor. A 3.3 volt signal from the sensor will still be seen as a logic high by the Nano so there’s no problem there either. 
I figured out why I keep destroying these vcnl4040’s. It must be because I am not converting the logic level of the scl and sda. On a side note, yesterday I drove 140 mile round trip to Mouser Electronics will call and purchased 10 more Sparkfun VCNL4040’s because I became impatient waiting for my delivery from Sparkfun. I should have paid for 2 day. Since then I think I may have damaged 3 of those 10 last night and 1 this morning before I realized I completely forgot about the clock and data lines. This explains why they would start working few a short moments in time then fizzle out.
With all that being said, I have 1 Velleman VMA410 logic converter. I have never used it before and am hoping to with the Sparkfun vcnl4040. I am going to attempt to hook it up using the wiring example from the Sparkfun level converter hookup guide…but as I take a closer look, I see that the VMA410 has only 2 channels compared the Sparkfun has 4 . I need 1 for the clock, 1 for the data, 1 for the power, and 1 for the interrupt. I originally purchased the VMA410 a year ago to use with an Adafruit HUZZAH32 – ESP32 Feather Board because I didn’t realize that was 3.3V when I first purchased that item. So maybe i should use that development board becaue I would not need convert all those lines. I am going to try that now.
After many hurdles I was able to load the Sparfun Example2_IsSomethingThere sketch onto the Adafruit HUZZAH32 – ESP32 and wire it up to a vcnl4040 only to find out the serial monitor is not available with the Adafruit HUZZAH32 – ESP32 via USB. So I can’t see anything and I can’t verify it is working that way. I guess I should be able to make an LED light up when it senses something there, but I really need to see the serial monitor data eventually, so what’s the point of that.
I am nearing the end of my rope here.
I guess disregard all my past babbling. Magically the serial monitor started working, so I am going to try and work with this set up and see how it pans out.
Does Spakfun have an example sketch for vcnl4040 utilizing the interrupt?
I see one with the APDS9960 examples but not the vcnl4040.
Sorry, we don’t have any example code that uses the INT pin unfortunately.
How much do you want to get paid to help me get this interrupt functioning? I am serious. For you I believe it would take minutes. For me it will take weeks.
Unfortunately I can’t write code for you, but perhaps someone else reading this thread can help?
I understand. How about if I put it this way.
The Sparkfun Example2_IsSometingThere.ino code does exactly what I need it to do, except for one thing. I doesn’t trigger the interrupt. That’s all I need to figure out. So my question or questions are:
What line of code tells the VCNL4040 to make its interrupt pin go LOW?
What line of code tells the VCNL to make its interrupt pin reset back to HIGH?
Have a look at lines 47 through 51 of the Example5_AdvancedSettings in our library. That shows how to set the thresholds for toggling the INT pin but the sketch doesn’t actually read this pin. For an example of how to read an interrupt, have a look at the links below.
Google “vcnl4040 application note”.
Vishay has several