#141

[@andyfraser5876]

It's all to do with the shutter on your camera conflicting with the refresh of the screen. If you put some neutral density filter over the display and reduce the lighting, the camera will increase its exposure time for each frame and the flicker will reduce or disappear.

[@RalphBacon]

It's doubtless to do with the shutter speed, Andy, but I could not fix it doing it your way. But, see the pinned comment at the top of these comments! Great to hear from you, thanks for posting.

[@garymiller3542]

Hi Ralph Thank you for the Esp32 with ssd1306 library. I spent many hours getting the older display to work with a Esp32, and was have problems as other library would not compile . Then I tried your ssd2306 library and It worked. My esp32 development board that I designed. On easypcb now has a fully functioning display.

[@RalphBacon]

Great news, Gary, so glad you got it working.

[@chrisw1462]

What you're calling 'blur' is usually referred to as blowout - the display is too bright for the camera exposure setting. As you saw, when the bright light was reflecting off of the display, the text you could see was sharp. When you shaded the direct light, the camera opened it's 'iris', and the text got 'blurry'. I really can't wait to try one of these for myself.

[@RalphBacon]

Yes, I agree, and I find it really irksome that my camera doesn't give me more manual control. I'm fighting it when it comes to filming almost anything that emits light, rather than reflecting it. I shall try a few more things out. Thanks for posting Chris, worth checking these combo ESP32/SSD1306 modules out, certainly.

[@Chriva]

I don't think many library makers actually care about the specifics of the OLED panel. ssd1306 has one heck of a lot of registers one can set to configure how the panel should be driven :)

[@RalphBacon]

I delved into the Adafruit library, Christian, and it was horrible. No wonder they (and others) have created libraries otherwise they could never sell any of these SSD1306 screens to standard Arduino users!

[@Chriva]

@@RalphBacon I definitely agree but given how many products they sell it is kind of expected. :) I tend to just roll my own stuff most of the time but I can certainly understand those that just want stuff to work (It's like 99% hair pulling and 1% enjoyment when you do it yourself). Great video as always, Sir :)

[@RalphBacon]

*REMOVING THE VIDEO FLICKER* I've pinned this comment to respond to everyone who has suggested ways of *removing the flicker* on my video camera. Thank you all. 🤗 Now read the rest of my post... I've tried them all. I even checked that the date was not 1st April and removed the protective strip to see if it really did make any difference. It did not. Michael, I'm pretty sure you were just pulling my leg! What *did make a difference* is when I put my camera on FULL AUTO (rather than the usual 100-videos-later, semi-manual mode so I can increase the exposure a bit in my workshop if required) and the flicker disappeared completely. 😳 So from now on, I'll let the video camera do its thing on full auto and we should never see another flickery screen again! Thanks to everyone who has suggested ways of doing this (and all those who don't read others' comments and have suggested stuff after this was posted!).

[@RalphBacon]

I've just responded to Duncan in a comment below: ...my camera doesn't have a full manual mode and insists on taking control of the shutter speed (it's a video camera not an SLR-type one).... otherwise I would have, most certainly.

[@stevenheynderickx583]

Ralph could you explain how to display an integer on to the screen? Love your videos by the way. I use them as preparation for my lessons.

[@RalphBacon]

Convert the integer to a String and send it down the wire. You can use String number = String(myNumber); or try the built-in "itoa" function. (Integer to Alpha conversion).

[@gpTeacher]

Hi Ralph: I hope you had a great time in Germany. I've started playing with the ESP32 Camera module I got off banggood. It's working fine with the basic Camera Web server sketch. However, as I do not have an FTDI programmer, I used an Arduino nano as a TXRX terminal to do the programming. I wired it as follows: Arduino Nano ESP32 +5V -----------> +5V GND -----------> GND TX1 -----------> U0T RX0 -----------> U0R Arduino RST shorted to GND ESP IO0 to GND for programming mode When I upload the sketch all works fine. Then I disconnect IO0 from GND and press the reset button on the ESP32. If the RST and GND on the Arduino are still shorted, the ESP restarts, shows the startup sequence in the Serial Monitor and grabs an IP address and I can access it from a browser. However if I have NOT got the ARDUINO RST pin shorted to the ARDUINO GND, it will not reboot. Any suggestions as to how I reboot without the RST shorted to the ARDUINO GND are appreciated. I want to build a wifi controlled robot that I can drive via the web browser while watching the video feed. Without the ability to reboot, free of an attached Arduino, it's not going to be very successful. Thanks for your thoughts Ralph. Gord

[@RalphBacon]

I just want to clarify here your wiring, Gord, when you say Arduino RST is shorted to GND. That would bring the Arduino into a permanent reset state (ie stopped, not running) as the power is disconnected (I think, I never thought about what the actual state of the device is whilst it is pressed). Certainly GPIO0 must LOW for it to enter bootloader mode. Are you sure you have a bootloader on the ESP32? I've never done it this way so I'm struggling to suggest things. Other than to buy an FTDI or similar USB to Serial device (just $2-3) and do it that way, then you will know if your ESP32 is working as it should. All my ESP32 have USB sockets to I program them the same way I do an Arduino.

[@gpTeacher]

@@RalphBacon Hi Ralph. Yes, the Arduino RST pin is permanently grounded. This video is what I followed to do the upload. kzbin.info/www/bejne/l5CzqXSKbbJga5o At timestamp 1:24 you'll see the wiring diagram I followed. It uploads and then I remove the wire from IO0 and press the reset button on the ESP32. But it will only reboot if the RST pin on the Arduino is still connected to ground. Once it boots, I can remove the RST pin. I want the ESP connected to the Arduino so I can see the status messages in the Serial Monitor and get the IP address for the ESP32. I have an FTDI on order. Was just trying this while I await its arrival. Thank you for your assistance Ralph. Have a great evening. Gord

[@gpTeacher]

Just a followup. I do have a ST-Link V2 Programming Unit mini STM8 STM32 Emulator Downloader that I bought for an STM32 but I haven't used it yet. Would that work to program the ESP32? If so, how do I wire it up? Thanks

[@RalphBacon]

Not sure about using the ST-Link for the ESP32; I've only ever used mine for an STM32. When you say the ESP32 doesn't boot are you sure or are you just not getting the serial output? The way I code things to make sure about this is to put a simple beeper on a pin and beep it twice in the setup() routine so I know it is running (or not, in your case). An alternative would be to use an ESP32 with a standard USB socket already connected up whilst you experiment and then swap to your current ESP32 (assuming you are using that one for a reason). Final question: is the power supply up to running both Arduino *and* ESP32 (by resetting the Arduino it will not draw power).

[@gpTeacher]

Thanks Ralph. All great suggestions. I’ll give them a try. Definitely the beeper and more power. Thanks again!

[@williammiller7543]

Thanks for another Great video, very informative. I notived this board has a LOT LESS pins than some other ESP32dev boards? I know on the ESP8266 dev board there are several pins that are brought out that we shouldn't really use. Is this why less pins on this dev board?

[@RalphBacon]

I'm not sure about that, William. There are some pins that are used to address FLASH memory but I don't think that accounts for them all. I shall keep this question in my head as I explore the ESP32 more in future weeks (I love this chip, better than the ESP8266, as you'll find out in a couple of videos' time).

[@tomgeorge3726]

Ralph, I have ESP32 units that do need the boot button presses and some that do not need the button pressed. It doesn't matter if it has the display or not. But I believe the non boot button. I have TTGO ESP32 and I think they are the non boot, with ESP Dev Board, selected in the Arduino IDE.

[@RalphBacon]

It's not exactly a deal breaker, Tom, but it can be quite irksome when you're uploading version 8,481 of your code and then forget to press the button and have the upload fail (again)! This board wins for me with its built in display all on one board but we can do the same using other SSD1306 boards and an ESP32 board that doesn't require the BOOT button to be pressed, I'm sure.

[@gavinsmalley1513]

Daylight saving time is a mess! Truly a mess! The only reliable way I've found is to use ezTime instead of Time and rely on the tzdata lookup. YMMV though. Your skillset is far beyond mine.

[@RalphBacon]

The ESP32 (and ESP8266) have better ways of doing this, apparently, so I shall be checking all options. MY (rather long-winded way) works beautifully though!

[@Ed19601]

Can I find something more on yr home alone project somewhere? I guess the name already suggest something. I started my endeavours in home automatisation initially from a point of imitating my presence when I wasn't home (before the ESP era), so I am just curious what your project is

[@RalphBacon]

I will be coming clean about my Home Alone project (now renamed to SmartCare ®) in a couple of videos' time, Ed. As you say, the name sort of gives it away. It's a (very) poor man's version of Hive Link, which I didn't know existed but it isn't what I want anyway): www.hivehome.com/services/connected-care-hive-link

[@pintokitkat]

Coo, a ghostly, see through Ralph!

[@RalphBacon]

In the interests of full (partial?) transparency, and I guess you could see right through me anyway, I'll put this down to an overzealous Green Screen processor! 😂

[@pfeerick]

Did you ever get to the root of the daylight savings issue? I've been using that 'built-in' form of NTP of late on ESP8266 as time libraries were causing me too much grief, and after going around in circles for a while, settled on an implementation that seems to be stable. In my case, I specified `configTime(0, 0, NTP_SERVERS);` ... so no timezone, no DST offset, and an array of local & international NTP servers ... using `setenv("TZ", "AEST-10", 1);` to set the timezone. My timezone spec is simpler as we don't have DST in our state... maybe in your case it was something to do with DST starting... specified as being from the last Sunday of March to the last Sunday of October in your example if I'm reading that right? Maybe the start and finish hours needed to be specified also? i.e. `setenv("TZ", "GMT0BST,M3.5.0/01, M10.5.0/02", 1);` ... I'm hoping that's all it is... else other people will have some grief if they use code I write using that NTP functionality and need DST, etc! :-O Loving your videos btw! :)

[@RalphBacon]

I _think_ I got it all setup OK, Peter. The problem is testing it. At work we had a particular piece of work all completed and then October 30th rolled over (last Sunday) and kaboom, all the times were wrong. Oops. After that we were constantly setting our Windows PC with different dates (GMT/DST) to test it all still worked! To see... To see my actual code (which has to switch between UK and European time, as well as cater for DST, just to add to the complexity) look at my GitHub for the Home Alone project and find the *time_t getLocalTime()* function - it's too long to post here. It uses a *TimeChangeRule* that defines when DST is in force for a country. Also this little snippet must not be forgotten: // See Arduino Playground for details of this useful time synchronisation library #include #include Here's the link to that GitHub repository: github.com/RalphBacon/ESP8266-Home-Alone-Vulnerable-Person-Monitor

[@pfeerick]

Only had a quick skim of the pertinent bits so far - but I see you've gone back to the 'old' way of doing NTP lookup, and are using TimeLib again, so it's nothing like the built-in NTP routines. Certainly one of the harder things to debug unless you have your own NTP server running that you can change the time on to see what's going on! Hadn't seen the TimeChangeRules before, which looks quite handy. Now to watch this video about an ATMEGA328P clone on steroids...

[@andymouse]

Hi Ralph, very interesting stuff, I think I shall have a look at the Esp with screen ,thats great value. One unrelated question, how do you examine library's...the ".h" files and ".cpp" files this is something I never get down to as I tend to roughly sort of work it out from examples (ish) it would be useful to see how the functions that I call are built, and have a go at understanding them, as an example have a look at the Adafruit .h and see what it does...if your busy could you pass this on to Benny....cheers!

[@RalphBacon]

A library's header (.h) and c-plus-plus (.cpp) files are just text source code files exactly as you might write. They get compiled into your sketch as though you had written them (you wish, hey?). You can open them using the Arduino IDE (just double click on them). If you write your _own_ library, create the two files in *the same folder* as your sketch then the Arduino IDE will open them automatically with your sketch. Any help?

[@andymouse]

@@RalphBaconHi, very much so, its a topic ive neglected till now, and yeah I DO wish !...……..Thanks!

[@andymouse]

@@RalphBaconMe again! just been poking around in my sketch folder and opened some library's from there, but I still dont get how to view them from within the IDE (double click on them) and have them appear as tabs to view at my leisure. is it something to set in preferences ? as I can't double click on anything and see the two files I'm after...what have I missed?...your vid on "creating library's" has been a great help too.

[@RalphBacon]

Hmm, the Arduino IDE is playing silly bug**rs. I don't have this issue in Eclipse. Place a copy of the library (.h + .cpp) in a folder with a blank sketch and then open the sketch. The other files should open in different tabs in the IDE.

[@andymouse]

@@RalphBacon TA-DAA !!… Yep, thats what I meant, shame there isn't a slightly easier way than that because as your confidence grows it would be very useful to have a look at how these mysterious functions that we call, use and love so much actualy work. This all came about because I've been digging around in the world of "Micropython" and "Visual Studio Code" and as of 30 mins ago "PlatformIO" and I like what I see, however a intensive course of command line work and file handling with a dash of path structure is necessary as I have realised just how much of the "heavy lifting" our beloved IDE does (you moved on years ago!)….anyway thanks for that. If there is an easier way please let us no, also are you interested in any of the above ?

[@Mr_Gadge]

Hi! Just a thought for a video! :) I have a 3d printer. There are a few points of concern for overheating such as xt60 connector, the PSU itself and the motherboard.. I'd love to have such as a wemos wired to this 1306 type with 3 lines of temps, board/connector/PSU, and have an alarm if they go over a certain temp? simple buzzer. I have all these parts and no bloody clue where to start lol so any pointers, or if you fancy becoming really popular with 3d printing I thought it may be a great idea for a project. A simple holder for the screen could mount to the side of the printer, which I can design in fusion360. I don't think I'd want the shield OLED so that it's just the screen that's visible. I'd take your advice on surface temp monitor, as I only have dht11/22 and bme/bmp's. So, any pointers or a good idea for a project vid? Many thanks for all your output so far! :) from a big time noob near Blackpool. Edit; this one went down quite well for print monitoring! kzbin.info/www/bejne/iJ6QnWR8iNp9pqs

[@RalphBacon]

Hmm, sounds challenging, William, but I shall add your suggestion to my list and see what happens. Regarding temperature sensors, for this application you need them robust and sealed so waterproof types of the DS18B20 type are good. They are quite cheap anyway but from Bangood they even cheaper and come with various cable lengths: bit.ly/2NjNdYO I did a video on this sensor (an unsealed one) in video #28 so if you get that working with just one sensor you are already partway there. kzbin.info/www/bejne/ooKzcpmAmN2Sp6c

[@duncanx99]

Alter the refresh rate of the display by using a "delay()" in the loop - play with the value for best results vs shortest delay time.

[@RalphBacon]

The (video only) flicker is not dependent on the screen update frequency, Duncan. Just to be sure I only updated the screen every 5 seconds but the flicker remained. Now read the pinned comment at the top!

[@duncanx99]

@@RalphBacon I has to be a 'beat' between the display and the camera 'shutter' but if the 'Full Auto' workaround doest the job, then stick with it...

[@RalphBacon]

Oh, definitely the 'beat', it's just that my camera doesn't have a full manual mode and insists on taking control of the shutter speed (it's a video camera not an SLR-type one). As you say, though, if full auto works then it works. Pity I had not discovered this _before_ the video but after an hour (no kidding) of trying everything (well, as it turns out, _almost_ everything) I gave up.

[@pfeerick]

Having the camera in semi-manual mode at least demonstrated that there was something causing flicker in the Adafruilt library that the Thingpulse library didn't exhibit... doubt they've fixed it... hasn't been any updates to the codebase in the last six or so months... very interesting!

[@artemnikitin2806]

imho the flickering is i2c bus speed difference, same thing when I was running bluepill+oled at default i2c speed - 100khz i believe, but after i bumped it to 400khz and later to 1.7mhz (i have other devices which benefit from faster i2c on the same bus) flickering was gone (flickering was only visible through camera) .

[@RalphBacon]

That's very interesting, Artem. Next time I dig this out I shall try increasing the I2C bus frequency if the LCD can support that. Thanks for posting.

[@bipolarchemist]

I will have to recheck my collection of code, but I believe you can just initialize the wire(I2C) bus to the correct pins and call begin as usual. I think I had to do this with a couple of BME/BMP280 sketches to get my sensors to work. I think I have one of these in a box that I've yet to play with so I might play around with it and update this comment on whether or not initializing the wire library with the proper I2C pins works.

[@bipolarchemist]

This is for the adafruit library. If you change the display declaration to Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET); and then call Wire.begin(SDA_PIN, SCL_PIN); display.begin(SSD1306_SWITCHCAPVCC, 0x3C); in the setup function, things should work with the stock library. I used the example from github.com/adafruit/Adafruit_SSD1306/blob/master/examples/ssd1306_128x64_i2c/ssd1306_128x64_i2c.ino without change save for calling Wire.begin(sda, scl); and I changed the default I2C address from 0x3D to 0x3C so I imagine it should work with your code as well, I just haven't given it a go yet.

[@RalphBacon]

I am positive I checked whether this: Wire.begin(SDA_PIN, SCL_PIN); worked but there were no parameters (or overrides) available. Perhaps I am using an older version of the library? I will double check this, as it seems such a common requirement. Thanks for the heads up, hmx, appreciated.

[@bipolarchemist]

@@RalphBacon I am using version 1.2.9 of the library. Hope that helps and glad I could pass along a useful tip.

[@MikeNewham]

Peel off the little transfer/sticker - cause i notice the one that does NOT flicker - because it has no protective sticker on it ??

[@RalphBacon]

It's not April 1st, Michael. See the pinned comment at the top!

[@jstro-hobbytech]

What is that ide you use. I remember you mentioning it but I can't remember which video.

[@RalphBacon]

I'm going to address the new IDEs soon, Joey. Don't use the one in my videos as it is no longer supported (but still works): eclipse.baeyens.it/

[@mortneff4674]

Your phone Cam talks the same mode, wherew as your other cameras see the flickering because of the different rame rate! I believe if you could get your cameras to record at the same frame rate as that board is showing it wouldn't flicker!

[@RalphBacon]

Agreed, but would you Adam and Eve it, my camera won't let me adjust the shutter rate. Expo6se, focus but not shutter speed. Doh!

[@mortneff4674]

@@RalphBacon Truth, but anyone who's tried to take videos of TV and other electronics should understand the problem but for some reason tech people who make the Cameras don't know how to fix it!

[@ddjazz]

What is the other arduino software he is using besides arduino ide ?

[@RalphBacon]

I'm using Eclipse Sloeber edition (that contains the Arduino bits).

[@peut]

On your time struggles. You forgot to use tzset() and config time should have 0,0 as first two arguments. In code: //Apparently config time is only reluctantly supported on ESP32 //better use the IDF // don't forget tzset() setenv( "TZ" , "CET-1CEST,M3.5.0/2,M10.5.0/3", 1); tzset(); sntp_setoperatingmode(SNTP_OPMODE_POLL); sntp_setservername(0, (char *)"de.pool.ntp.org"); sntp_init(); But, you can still use configtime // don't forget tzset setenv( "TZ" , ntpTimezone, 1); tzset(); // leave first arguments to zero, that's where TZ will jump in configTime(0, 0, "nl.pool.ntp.org");

[@RalphBacon]

I shall play about with this over the next week, Jose, thank you very much for posting this, greatly appreciated.

[@peut]

@@RalphBacon You may want to check out github.com/gitpeut/esp_sntp. I primarily saved it for my own purposes after ploughing through lots of long discussions on the internet and lots of trial and error.

[@browaruspierogus2182]

This display could be programmed literally in 10 lines without Arduino using idf. It probably would be 100X faster no flicker

[@RalphBacon]

Well, you may be right but then again this is predominantly an Arduino channel and hence we're a bit limited in what we can use. But I got rid of the (video only) flicker, see the pinned comment at the top.

[@browaruspierogus2182]

@@RalphBacon I am just saying. Most people don't understand Arduino framework is not always compatible with ESP32. Besides Arduino runs on top of FreeRTOS

[@RalphBacon]

Indeed, and I'm glad you mentioned IDF Programming from Espressif. It's not something I'm familiar with but maybe I should be if I want to continue using the ESP32 chip in preference to the ESP8266. For anyone else interested here's the best page to land on: docs.espressif.com/projects/esp-idf/en/latest/get-started/index.html Thanks for replying, Browarus, you made me think twice about IDF!

[@gavinsmalley1513]

@@RalphBacon Maybe there is scope for an advanced video? Showing how to set up the ESP-IDF (and maybe even the ESP-ADF) in Eclipse? For those looking to take the next step? You are such a fantastic educator and have such a great presentation that I'm sure there would be an audience. You've nurtured do many of us along the way, and in sure will nurture many more to come. there will be a time when, thanks to your videos, we are no longer Arduino beginners!

[@RalphBacon]

Flattery will get you everywhere, Gavin. I'll take a longer look at it and see if it has legs. As we never used to say in business.