I am curious about the Program-Erase cycles
is the size of them always 512Bytes, in all microSD cards no matter the card's capacity?(meaning this 512 number is defined by the manufacturer of the microSD card, in hardware)
Or is this number affected by the user somehow, for example when Formatting the card?(from what I remember from Format programs, you can only choose the Cluster size, not the Sector size..)
In SDSC (cards up to 2 GB), it's actually possible to change the block size to a smaller one (although it's done virtually by the card's controller), and write a single byte like an EEPROM.However, in SDHC (4-32 GB) and beyond, this is not possible anymore, and the block size is always fixed to 512 bytes.
The IC cannot and doesn't store anything, it is just used for Level Conversion, from what I understand.So when they say that using the CD4050 makes the module high-speed,do they say it versus using Transistors for Level Conversion, like we see in other modules (that support 5v and don't have the CD4050)?The Transistors are slower than the CD4050?
If indeed the CD4050 is faster than Transistors, I wonder if this extra speed is relevant to the speeds that we can get when using Arduino and a microSD card, which from what I understood are around 200KBps for writing, and 300KBps for reading..
I think I will also buy the module with the CD4050,for experimenting and comparing the max. speed it can give vs. the other microSD modules I have.
(when something costs 1$, it's hard to resist)
But isn't the CD4050 there as a level shifter - from 5V to 3.3V, not really as a buffer? I think most modules use the 74LVC125A, but the function is the same.
color TFT LCD displays, and e-paper displays
Or maybe you meant bigger sizes?
While reading and programming is performed on a page basis, erasure can only be performed on a block basis.
The pages are typically 512, 2,048, or 4,096 Bytes in size.
Typical block sizes include:- 32 pages of 512+16 bytes each for a block size (effective) of 16KB- 64 pages of 2,048+64 bytes each for a block size of 128KB- 64 pages of 4,096+128 bytes each for a block size of 256KB- 128 pages of 4,096+128 bytes each for a block size of 512KB
They say that writing is done to a whole Page (e.g. 512B),but Erasing is done only on a full Block of Pages (e.g. 16KB, or upto 0.5MB...)This is now a much bigger problem than the 512B that we worried about, for a page..
ideally the sd/microSD card's blocks should be Erased beforehand
I wonder if regular Format programs, (when not choosing the Quick Format option),do the required Block Erasing operation, when recognizing that the media is SD/microSD card..
If not, then a dedicated Format program could be helpful..
It does exist, and it's called "SD Formatter".