- Sat Aug 22, 2015 9:29 pm
#26840
Hi Ray,
This is not that simple ! ... On ESP but also on STM32 or other MCUs ...
Read/Write an external storage FAT storage via USB is much more complex than R/W on an SDCard via SPI.
To use such USB Mass Storage device over OTG Host USB, we need to use library such as
https://www.circuitsathome.com/mcu/mass ... 0-released.
But the current library implementation is also need dedicated hardware based on the MAX3421 such as Arduino Shield
https://www.circuitsathome.com/products ... or-arduino. But such shield cost more than US$10.
I've order one recently and received it last week, but didn't I've chance to try it out.
Of course, there are possibilities to have same functionalities done in software, I've also saw some libs under mBed environment, but I bet we can't get the best performance as an hardware solution. We should remember that embedded MCU environment is not the same as been behind a PC with Linux. It is quite the same thing when many people says that Wifi-USB dongle only cost $3.00, but their Linux kernel drivers needed for them can't simply be ported to an MCU.
Personally, this whole question of "OTG Host under MCU" is one of my future project, not only for ESP, but for also STM32
.
It won't be to challenge small storage size already provided by SDCard via SPI, but only a personal technical challenge to get a 3TB HardDrive hooked-up on an MCU, without any cost limitation perspective considered ...
