Overwiew
I am working on my first project with ESP32, I have ESP32 CAM model and I am creating an automatic roller blinds. I got most of the project working - I have web server that controls continous servo and all mechanics. I want to be able to adjust the time for going up-down without reprograming the microcontroller. The goal is to have an automatic roller blinds with alarm clock function.
Problem
I need a way to reliable save/read data to store variables state, even without power. How to achive it with ESP32 CAM?
Additional info
On Arduino board that would be EEPROM, and I found some tutorials that claim that EEPROM can be used on ESP32. However, when I tried using EEPROM, it looks like the values are overwritten while bootloading. So I guess ESP32 CAM needs different approach. Correct me if I am wrong, please.
Ok, so user bvguy on Reddit solved my problem.
"EEPROM is deprecated. They want you to use preferences now. Here is an example ."
I tested the example and it works on my ESP32 CAM, therfore solving the problem.
I recently started coding on a raspberry pi. I build a circuit with three buttons, an LED and a 7 digit LCD. Its a fairly simply thing. You can set a time value with the + and - button in seconds and then press the other one to start a countdown. I use this to do triggered long exposures with my camera. However the raspberry pi is to big and bulky and needs to much energy.
Then I put my code and my circuit on an Arduino UNO which is an improvement in size and energy consumption.
Because my program is very simple I am sure that there must be a way to get this on a much smaller chip. I need some kind of programmable chip where I can put my code onto. Something that is small and dont has any other fancy features or more calculating power than I could need. As far as my knowledge goes I dont have any idea how to get into that.
At work we have a 3D printer with a W1209 temperature relay controller on it. This is a small circuit with the same 7 digit LCD pane and the temperature is also settable with two buttons. This inspired me to look for something much more primitive that would be enough for my needs.
Can you recommend any hardware or some tutorials about that?
Search the Microchip website for the DM164141 - MPLABXpress PIC16F18345 Evaluation Board. I think it's around $12 and should have enough I/O for your application. You can use the online MPLABXpress IDE for development.
I'm building a temperature monitoring unit with arduino, LM35 and a 16*2 LCD display. Now I am going to integrate this unit by SIM900A GSM/GPRS module and I get temperature readings by SMS.
Now my question is, can I get those values by voice calling. If I called to the GSM modem, can it tell the temperature readings.
You need to add all possible values as .amr files or you can break them and play the appropriate files using at commands. Like for 35 you can play sound "thirty" and then "five".
Follow the AMR playing application note available here
Apart of having all the messages in PCM files there is also possibility to use TTS (text to speech) There are small and compact TTS engines out there suitable for Arduino port. Here two I am using (with AVR32):
Tiny Speech Synth by stan 1901
just port it to your arduino (removing the waveout stuff and just use the buffer as PCM). The only lib it really needs is math.h for sin,cos. It may need a bit more work to actually make it more comprehensible but its not that bad when tuned the frequencies ... its using floats heavily but I think port to integer math is also possible ...
KECAL 1.0 ports for ATMEGA
its much older TTS engine originaly from ZX Spectrum but its a bit less comprehensible especially with low quality reproductors (like buzzer) ... But id does not need PWM or DAC ...
I do not know of any more recent OpenSource TTS engine compact enough for MCU platform all I know of are too big or relaying on SAPI,.NET or other OS integrated stuff making them useless.
The #1 is simple and commented enough to make changes improving the phonemes. The #2 was heavily optimized for speed and size (it run on ~4MHz Z80) so no way to improve quality there.
Btw there are also IC for TTS out there so that might be even better choice...
[edit1]
Take a look at this:
Is there any text to speech program that will run on an 8- or 16-bit CPU?
Among other things I added there very good quality and low CPU demand TTS engine ported from Z80 asm into C++, which can be directly used by MCUs ...
Ive been trying to build a 32X12X12 LED cube (something like this http://www.youtube.com/watch?v=f1YNyQqbiF0 ) and trying to get some animation running on it. I used the Arduino to get a 8X8X8 cube running and i wanted to know:-
Is it possible to do the same with the Arduino (considering limited number of ports)?
If Yes, what additional hardware would i require? (Like Multiplexers and Shift Registers)
Is there a LED Driver or any other open source HW platform i could use to do this, that allows easy programming also?
I will multiplex your 3 questions into one answer: I recommend the MA72xx to drive your LEDs. You can drive up to 15 of them from your Arduino, which probably will suffice your 32x32x32 needs.
I would like to solder a microcontroller, control buttons and an DVI/HDMI output and program this in a way, that I can store images on it and let them display as a dia-show via the outputs.
It doesn't have to have a lot of storage capacity, 128Mb would be enough.
but I don't know how to start, because I haven't done anything like this before.
My aim is to present some important images to friends by just taking this hardware, connecting it to a TV screen and showing these photos. If should be able to switch the photos manually (using a button) or automatically in a dia-show.
It should support several TV resolutions and it should be connectable to my PC (USB prefered), so that I can upload and delete photos.
So where to start and how to do that?
Thank you in advance, Andreas
If your aim is just to show some photos, there are assuredly simpler and more cost effective ways to do so; devices exist which do more or less exactly what you are proposing.
If your aim is to learn about microcontrollers and this is a project your are taking up to further that, I would recommend looking into the Arduino: http://www.arduino.cc/ or a similar kit based micro, and growing your project from that.
Microcontroller + low level language will be a huge pain to work with, particularly if you wish to handle various file formats and screen resolutions. Get a full-blown computer with an OS instead - something like http://en.wikipedia.org/wiki/PC/104
If your goal is purely to be able to display photos then I would recommend using a digital camera with video out capabilities.
If your aim is to learn about electronics and microcontrollers I would start with a good book and an Arduino board. Note that writing microcontroller code to handle file systems, image formats and video output is non-trivial. Simpler projects may be a better starting point as they are more accessible resulting in quicker progress, less frustration and more motivation!
The engineering field is a interesting field. You can start with the web site "www.microchip.com". You will need a high end device consider the PIC32MX795L512, there is a nice starter kit for it, "Ethernet Starter Kit" http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=2615&dDocName=en545713. This kit has the on board debugger & programmer to do all the hard work.
You get sample projects with the package, you can program using ansi c programming.
IDE : MPLAB which is free, and the C32 compiler has a student/lite version.
Arduino also has a board with the same device.
I personally like "www.techtoys.com.hk", they have device compatible with Microchip boards like techtoys.com.hk/PIC_boards/PIC32STK%20SSD1963%20EVK/PIC32STK%20SSD1963%20EVK%20R1A.htm, or this techtoys.com.hk/PIC_boards/PIC2432EVK-RD4/PIC2432%20EVK%20RD4.htm where this board you will need a debugger/programmer like the low cost PIC Kit 3 "microchip.com/pickit3".
The trouble is you need to write the HDMI video library yourself, there are some VGA libraries available but they are only black and white and very hard to get color with these analog images. The rest of the libraries are already there, USB MSD(flash drive), SD Card, pictures (jpg) etc.
microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=2680&dDocName=en547784
Feel free to contact me if you need some help, I might be able to help with the HDMI library.
It's a lot of fun to play with these toys.
Regards
Lucas
B-Eng Digital Engineering.
imlucanio#yahoo.com (no spamming)
Remember to add the http and www to the web links.
It sounds like you want an iPod. That is a dead simple thing to work with and it does everything you want. Otherwise, very complicated. I'd suggest the BeagleBoard and embedded Linux. Yes, it warrants that level of complexity.
The options for small microcontrollers just aren't there. The Arduino is very popular and yes, you can interface an SD card to it. That'd be your storage. Yes, you can put a digital potentiometer on it, that can be your interface. I've seen some video overlays that do simple text, but never any JPEG display (too much processing required). And certainly no 24 bit color (so that the output would actually look good) - that would take WAY too many pins to do correctly (and the Arduino doesn't have a D/A converter! You'd have to rig something up that would suck). And even then, all of the options for TV out weren't HDMI, but RCA (the old red/white/yellow cables).
So in short, no. Get a computer. That's what can do the job.