Looking for resources about USB memories

[djalli]

USB Storage

I am very little familiar with these USB pen drives, mememory stick storages.

Can I have a better horizont for them, explanations, literatures?

 

[Andre3000]

USB Storage

search for flash memories !

 

[djalli]

USB Storage

They all are Flash Andre30000 in most of cases. Microcontrollers for example have Flash memory.

I disassembled a 16MB USB storage from CompUSA and not only had a flash memory produced by Catalyst but also a manual switch which I don know what is the role of it.

What to know any documentation of them.

 

[mobile-it]

Re: USB Storage

You can search for OTI-2168 (controller with USB interface) and Samsung K9F1G08U0M (NAND Flash -memory)

 

[Big Boy]

Re: USB Storage

They usually will have 2 main chips. One is a USB controler custom chip, and the other is a plain simple flash.

However, there are some flash memory that are best suited for 512-bytes sectors (instead of usual 64K sectors). The controler will probably just make the USB device look like an USB IDE controler.

CompactFlash are similar, but have a direct IDE interface. I opened one of those once and it had 4 chips (1 ASIC controler, and 3 regular 32MB flash memory chips with 512Bytes sectors, for total of 96MB). I would suspect that this is similar for USB memory devices.

 

[ericmar]

USB Storage

Is it possible to use FTDI chip such as FT232BM to build an USB storage?

 

[anto2]

Re: USB Storage

what's there to explain, there is an sie (serial interface engine), a bit of firmware and x amount of flash memory. there is nothing really more to it unless you really wanted a detailed explanation.

 

[pisoiu]

Re: USB Storage

I disassembled a 16MB USB storage from CompUSA and not only had a flash memory produced by Catalyst but also a manual switch which I don know what is the role of it.

Almost all these devices have one switch used for write protection.

Is it possible to use FTDI chip such as FT232BM to build an USB storage?

No, FT232BM is used for serial data communications. The controllers inside the USB storage device are dedicated for this function and they have a direct interface with non volatile high capacity memories. FT232BM has a simple 9 wire serial interface as output, and is capable to transfer data up to only 921600 bits per second.

/pisoiu

 

[djalli]

Re: USB Storage

Almost all these devices have one switch used for write protection.

/pisoiu

You are right! I never tested it, I left as it was since I bought 3 years ago and only used twice.

I have 3 other ones with 128Mb space, they do not have switches.

thank you pisoiu.

 

[Big Boy]

Re: USB Storage

An FT232BM isn't suitable, but you could do it with an FT245BM. However, a few of the big things to do would be:

- Design an hardware interface, like a micro-controler, that interface between the FTDI module, and the memory
- If you wish the device to be seen as a drive, design a device driver, involving deep knowledge of Windows DDK.

If you wish to design a custom interface, like a simple program that you could use each time you wish to load and save data, without requiring the device to be seen as a drive, by Windows, then it would be much simpler. Note though that you'll need your program on each PC for which you need to use your device.

 

[Compy]

Re: USB Storage

want to design my own usb flash disk with samsung's nand flash memories..

need schematics and help