Hi ArduCAM-Team,
I’m using the Arducam-Mini-5MP-Plus(OV5642) with an Adafruit Feather M0 board. With this I’m facing the “SPI interface error”.
I use your example sketch for the normal 5MP-plus functions. The SPI is wired to the standard HW-SPI bus of the board. CS pin is adjusted to pin 12.
When I connect the OV5642 to an Aduino Micro (ATMega32U4) everything works well, no issues. I’m quite sure that this is no CS-pin issue on the Feather-board, since I always adjust the CS pin declaration accordingly. On the Feather-board for instance, I’m using digital pin 12 for CS.
I went through the few posts that exist and found maybe these possible reasons for the error:
-
Feather M0 (SAMD21) uses 3.3V logic, the Cam is connected to a 5V supply and hence might require 5V level on the SPI/CS pins?
-
Feather M0 (SAMD21) runs on 48MHz, hence the SPI clockrate might be too high for the cam (8MHz)?
-
The cam module requires 300mA and is fed in my setup by 5V through the USB output voltage pin of the Feather-board (supporting up to 500mA). In post
https://www.arducam.com/forums/topic/frequently-asked-questions-faq-about-arducam-spi-cameras/#post-14429 you stated that another board (the ESP8266 Nano V2) isn’t capable of delivering the requested current strength and hence the SPI communication fails.
So for point 1: Do I need to add a level shifter on the SPI bus? The Feather-board is not “officially” 5V-proof, but I saw that it withstands the 5V input levels. On the way out to Arducam, I would assume that the 3.3V level should be sufficient to still drive the SPI on camera side. So I wonder wheather I really would need a shifter at the end.
For point 2: How can I check which max level for the SPI clockrate is used? I’m not able to find this in the code. Can you give me a hint wheather this could be an issue and where I can check this?
For point 3: In the spec for the cam you mention that the cam can operate at 3.3V - 5V. Should I better connect the cam power supply to 3.3V instead of 5V? Does this cause even more current draw?
Thanks for your help.