Added the OC pin usage of CH422G

[H-sw123]

Verified on waveshare ESP32 S3 Touch LCD 4.3B.
Arduino IDE Serial Monitor:

Hardware connection：

Added control interface for pins 8~11 of CH422G.

[Lzw655]

Hi @H-sw123,

Thank you very much for your contribution. I reviewed the method you implemented, and it is quite good. However, I have the following two thoughts:

1. For common IO expanders, the OD register does not seem to be a universal hardware feature.
2. For the OCx pins of the CH422G, would it be more appropriate to treat them as general-purpose IO for control?

Also, quite coincidentally, I just implemented such a feature as well, and it’s in another PR #6 . If you're interested, could you please help me review and test it? Thank you very much.

[H-sw123]

Hi @Lzw655 ,
Due to other work reasons, I replied late.
Today, I tested the modified code in #6 and found that I could not set the working mode for 0-11. After I modified it, the test passed, and I found that enableOC_PushPull() and enableOC_OpenDrain() had no effect, and OC import could be directly controlled for output.
The code I verified has been synchronized to #7
If the code is not standardized, please modify it. If you need me to cooperate with other tests, I am very happy!

[Lzw655]

These modifications are very well-structured, thank you very much for your contribution!
I have one final suggestion: considering that TestCH422G.ino is only used for CH422G, we can directly use ESP_IOExpander_CH422G, which would eliminate the need for using static_cast<ESP_IOExpander_CH422G *> for conversion.

[bondango]

Verified on waveshare ESP32 S3 Touch LCD 4.3B. Arduino IDE Serial Monitor: Hardware connection：

Added control interface for pins 8~11 of CH422G.

This version worked for me, i was able to switch on and off a 12v light bulb ok via the OC outputs