I returned to my quest of getting the Arducam Mega 3MP working anf have had no luck at all. I have created the following diagnosis program that might help someone else here:
My latest attempt was with an Arduino R4 WiFi and all I keep getting is connection failures and incorrect reads. I have tried various wiring changes and testing but still no luck at all.
I used the above wiring but to no avail. The code uses pin 10 for CS, which also doesn’t seem to work.
The result indicate it is detected by any reads and writes come back wrong. I have tried all sorts of timing changes to no avail. Thus, I’m going to shelve this for a while and move on with other things.
It really shouldn’t be this hard and I can only think that perhaps the camera has somehow been damaged in all my testing. Perhaps a new one and fresh start is in order?
The next step in my plans was to add vision to my environment. For this I selected the Arducam Mega 3MP camera, which seemed to be straight forward enough from the initial research that I did. That has turned out to be significantly wrong.
I started off with trying to connect the camera to the ESP32 S2 Wroom but that was an abject failure. I then decided to move back to the Adafruit Huzzah ESP8266 to eliminate challenges with the ESP-32 S2 Wroom. Even this has proved challenging. Here’s what I have achieved so far.
The first challenge is to understand the SPI interface, which I haven’t dealt with before. You can read more about the SPI interface here:
Serial Peripheral Interface (SPI) is a synchronous serial data protocol used by microcontrollers for communicating with one or more peripheral devices quickly over short distances.
In essence, I needed to correct connect the Arducam Mega 3MP camera SPI interface to the Adafruit Huzzah ESP8266 SPI interface. The Arducam Mega 3MP camera pinouts look like:
and this is how I connected it to the Adafruit Huzzah ESP8266
1. CS (Chip Select) -> GPIO16 (or any available GPIO pin) (D4)
2. MOSI -> GPIO13 (D7)
3. MISO -> GPIO12 (D6)
4. SCK -> GPIO14 (D5)
5. GND -> GND
6. 3.3V –> 3V
VCC (3.3V) and GND for the camera I have taken from an external power supply source.
With all that now wired up, the other trick is that you need to have something to receive and display the image from the camera. All the demos I saw pointed to a Arducam GUI tool:
to capture an image which seemed to work without any issues when I looked at the terminal messages and execution. Problem was, I could now capture an image but I couldn’t see it! I needed to send the image somewhere to view it. Rather than use the Windows app I thought I’d send it to an adafruit.io dashboard.
Once I had set up a dedicated feed in adafruit.io and a dashboard with an image widget I used this code:
to try and send it. Unfortunately, I could see the code was executing and uploading to adafruit.io but I was getting feed errors. Some data had indeed appeared in the feed but an image wasn’t displaying. I also found that the Adafruit Huzzah ESP8266 was getting some sort of major error causing it to reset regularly.
After some investigation, it was recommended to disable the history on an adafruit.io feed to allow for greater data transfer sizes. The documentation tells me:
While history is turned ON, feed data is limited to 1KB (1024 bytes) in size.
While history is turned OFF, feed data is limited to 100KB (102400 bytes) in size
To do this go into the adafruit.io Feed and select the COG next to the Feed History heading as shown above. In the dialog that appears set the history to OFF as shown.
The other thing that I noted was:
The uploaded images appear to need to be base64 encoded.
I have some new code to try and overcome all of these issues which I’ll now go and try.
I’ve decided to upgrade the remote controller for the robot. Adafuit.io has the above component you can add to your dashboard. This provides a lot more commands than the original
one that I have been using as can be seen above.
My plan now is to add a pan and tilt camera to the robot so it can ‘see’. I’m also working on creating some additional parts for the robot to hold the 6V batter case as well as make the front platform more accessible. I’ll basically place it above the 6V battery which will sit over the front wheels.
I am also working on a way to better secure the bread board onto the robot rather than using a bulldog clip. It is all getting rather crowded up there, so creating some more space will be good.
It seems like the camera interfaces to the ESP32S2 Wroom using a set of SPI connectors which are:
Once I get it all connected then I need to write to code to capture images. There are lots of examples of doing that with an app on your desktop but I want the camera to capture an image and send it up to adafuit.io which it seems I can do. No sure of exactly how just yet, but first step is getting the camera hooked up and being able to view the images it captures.
CIAOPS Labs 
