Jinx wrote:
> Xiaofan, a client has asked if a USB memory stick (which I think
> is what you're calling a thumb drive) can be added to a 4550 to
> log analogue readings and general data
>
> I've had a look through some of the links you provided, especially
> those that mentioned mass storage. I'm aware that the 4550 is not
> a host, as you point out in the quote below. Do you know if anyone
> has a work-around ? Perhaps a peripheral adapter ? A thumb drive
> would be most convenient for end users (write with PIC, read with
> PC) so I'll pretty much do what it takes if it's possible

The short answer is a 18F4550 isn't going to talk to a thumb drive.  I would
need a external USB host controller since the internal one is only for
implementing a device.  Those exist, but you'd also have to implement the
USB host function in the firmware, or at least the on-the-go subset.  Some
PIC32 do have USB host capability.

How about something like a digital camera memory card?  Those can usually be
talked to via SPI.  You'd still have to do the FAT file system in fimware,
but that's a lot easier than a USB host driver.  Memory card readers are
cheaply and readily available for PCs.


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