Acquire SD card

[elpiel]

I've come to realise that in version 0.5 in order to acquire the SD card you need to call check_init or acquire but it's not exposed from SdCardInner.
Instead you need to call either num_bytes or directly try to read/write to the SD card in order to initialize it.
It would be nice to be able to expose acquire or better the check_init function in SdCard in order to be able to initialize it upfront before the first read/write takes place.

[jonathanpallant]

In theory any API call will trigger card acquisition. The demos just use num_bytes() because it's a nice one to print out.

[jonathanpallant]

Ok, I forgot to do it in get_card_type()

[elpiel]

Yes, it would be nice to have it also in the card type method.
My only concern of the current acquiring card method is that it is implicit.
This needs to be well-documented or have a separate method to initialize the card imo.

I've tested it today and I can't say how much improvement there is, however, new version is working 🙌

[jonathanpallant]

It's a replacement for the Arduino SDFat library, so keeping it simple is good.

[elpiel]

@jonathanpallant should I close this issue or should I leave it because of the get_card_type()?

[jonathanpallant]

I opened #90

[elpiel]

Ok, great!
Then we can either close this issue or set it to "documentation needed". I still believe it should be mentioned that it acquires the sd card on first call in the docs.