How to write data in USB flash memory using micro and RS232?

[Rodres]

usb mass storage interface ic

Hello

Could somebody tell me how can I write data in a USB flash memory using a microcontroller and a rs232-USB converter?.

At logical level, which is the protocol to write data in this memory?.

Thanks.

 

[pixel]

Re: USB mass storage help

You would have to implement USB protocol for mass storage device. I have not found such data, and even if I had it would not be so easy.
If you need to store data much better is to use SD or mmc cards, for which you need spi communication, and have lot of examples, and is much easier.
Also you could try with Compact Flash.

 

[metao]

USB mass storage help

you need firm ware for mass storage device class.
and you need hard ware for interface with
USB protocal (Called SIE = serial interface engine)
#not a good idear for develop SIE by yourself#
I suggest you use MCU that integrated SIE.

 

[amazonite]

USB mass storage help

I suggest you have to understand the FAT16 or FAT32 format.If you want to write data to usb mass storage. you can use bulk transmit via usb to the endpoint.Then write the data into flash memory in FAT fromat. You maybe can get some example code from the cypress's web.Good luck for you.

 

[djalli]

USB mass storage help

The problem is not FAT, NTFS etc formats for various filesystems but is there is very little information on these devices.

I know how you can communicate with USB devices in particular there is a book also "USB by Example" but there is no coverage of USB mass storage devices in this book or any book I can think of.

 

[Rodres]

Re: USB mass storage help

Ok. Now I now that if I want to write data in a USB flash memory, I have to do this using the bulk mass storage protocol, and I have to understand the FAT16 or FAT32 format. But I have a few options for implemented this in a device:
1. By using a microcontroller with hardware implemented USB interface.
2. USB implementation into a microcontroller through emulation of the USB protocol in the microcontroller firmware.
3. Using some universal converter between USB and another interface like ft2232BM.

I'm a beginner in this (sorry for that), so the only possible choice is using a FT2232BM IC, but How can implemented the bulk mass storage protocol using this IC and a microcontroller whit a serial interface?. This chip does everything or what I have to do from the microcontroller?. Can I use this IC in a device and let it work like a host?

Thanks.

 

[amazonite]

USB mass storage help

Please reference the Cypress's EZ-USB Series. I think you cannot use ft2232bm in the mass storage application.

**broken link removed**

 

[davorin]

Re: USB mass storage help

Ehhm...you want to attach a cheap USB storage device to your microcontroller????

If so -> forget it that it can be done in reasonable time and with reasonable effort..what you are talking here is connecting USB device with USB device which never works!!!!

You need to have a USB host on your microcontroller side...and there is no microcontroller with integrated USB host as far as I know.

Cheapest way would be to use the SL811 USB host chip from Cypress...next level would be some USB host chip from Philips.

And then comes the USB host driver part with all the enumeration process. No fun here...believe me (o;

 

[SAV]

Re: USB mass storage help

Maybe you can use some USB driver opencore thinking in a FPGA or CPLD design, using some HDL you can get a lot of choises for you design.

Somebody could help you findng the opencore.

 

[SAV]

Re: USB mass storage help

Hey guys, me again!!

Did you find usefull information here?. Check this link:

hxxp://www.altera.com/products/ip/iup/usb/ipm-index.jsp

Here you will find some USB opencores and tools.

Hint: 'x' means 't'

 

[davorin]

Re: USB mass storage help

Those are evaluation cores which Altera names "OpenCore"...
Nothing to do with opencores (o;


Altera released only few of their cores for free (aXXXX).