STM32: ethernet w5500 with plain (HTTP) and SSL (HTTPS)
OPEnS is with a quiet amount of resources, allows standard Arduino Ethernet to use secure connections.
Software Apps and online services
STM32F1
STM32F4
STM32 | w5500 |
---|---|
PA4 | CS |
PA5 | SCK |
PA6 | MISO |
PA7 | MOSI |
3.3v (better with external 200mha) | VCC |
GND | GND |
Retrieve certificate
To use an SSL, we need the server certificate, but in this case, SSLClient uses a trick given by BearSSL implementation. This minimal x509 verification engine allows using of Trust Anchors.
I add a simple online generator that you can find here.
You must only write the site’s address (httpbin.org) in the first input box, click Generate code
, copy the code, and put it inside a file called trust_anchors.h
and put it inside the sketch folder.