PureBasic Forums - English

Hi guys, I have an old Samsung cell phone which connects to my PC via the
serial port so I can download data off it. However, the software that comes
with it (EasyGPRS) only lets me take the photos off it, and not the videos.

Being a programming group, maybe someone here knows how I could read
the serial port to access all files on it, or maybe know of some software that
can treat a serial port like a folder that can be accessed under My Computer?

Would a serial to usb adapter do that?

Even if you could communicate with the device how would you read the file system?

That's what I'm asking.

I'm fairly experienced in the COM area, especially with mobile communication devices. I have been working mostly with Nokia phones though and had written a small wrapper for the Nokia 9110 Communicator, which allowed direct point-to-point protocol access to the system files under Linux v2.4.

Most COM devices work with point-to-point protocol and I do remember with the older Nokia devices, that the Nokia sent an ID to the PC. The Nokia software on the PC validated the ID and sent back a request for data access. Problem with this design is that only user accessable data (that is, no access to system files or ROM) was seen by the software. In most cases this includes only a memory card, but no access to the internal memory.

I don't remember the page, but I was able to write the wrapper for Linux with some help. In English the Nokia 9110 Communicator sent an ID to the Linux serial device, but Linux could not request access (send the data back). After some research I came up with the idea of breaking the master key. I scanned the ID of the Nokia, combined it with the master key and sent it manually back to the Nokia. The Nokia responded with an open point-to-point protocol access to the internal memory and the memory card. It was the first time I was able to access anything other than the memory card on the PC side. The master key of course, had its own encryption. The site where I got the info for the COM protocol also had a small bit of information on the master key. It was a simple hash that was reversed quickly once the generation technique was solved. After the master key was decrypted, I was able to swap the upper bytes to 1s from 0s. Once encrypted again and sent to the Nokia, I gained access to the ROM. I was able to send raw code to the AMD processor of the Nokia though my knowledge was too limited to write true homebrew.

Then I combined everything into a Bash script that emulated the Nokia into what is known as Nokia Service Mode. In this mode there is access to everything even the ROM containing the OS as it is intended to be used by Nokia to repair possible damages in low level.

Service Mode had its quirks though, the communication speed was limited from the 500KB to 50KB per second. I heard it is due to additional CRC checking that is done online. The Nokia was very complex, but I'm now happy with my Nokia 5500 Sport. Much simpler and supports the Pop-port interface.

I might be able to help you, but I need to know EXACTLY which Samsung it is, which COM protocol the connection is used and which cable are you using. Also if possible, can you tell that is the connection based on point-to-point access? I don't know how all this can be done in Windows, so you're on your own I guess.

Cheers, Irene.

I know there's a number of programs out there that can pull just about anything off a cell phone.

Try doing a search on Google for "universal cell phone software"

Tipperton wrote:I know there's a number of programs out there that can pull just about anything off a cell phone.

Try doing a search on Google for "universal cell phone software"

Yeah sure! Yeah, go on PB and download such software. Oh, but don't come back whining about it not working with your mobile phone and what I hate more than cold coffee are whining men ^.^

PB it's the pure cold fact that for your particular mobile phone there must be a particular software application that does what you particularly want it to do in a particular way that gives you that particular result you are looking for. Overuse of particular? Maybe.

What I am trying to say is
a) you don't need to know how to hack serial COM devices. I just brought it up to tell you I am knowledgeable in the area so I can greatly help troubleshooting any problems.
b) don't trust universal applications unless they specifically list that your mobile phone is fully supported (never trust "reported to work" stuff)
c) if you are serious about this issue and you really want help, then take note of the exact model of your mobile phone *and* what is exactly written on the serial data cable. You don't know how important it is to know if you have a genuine data cable, because the cable is what connects to your mobile phone and enables various functions (yes, there are some cheap alternative OEM cables which do not fully implement all possible functions of the connection)
d) take a deep breath and make sure you have set a goal that is within the frames of possibility. The type of connection used with the data cable might not enable browsing functionality so you can't view your mobile phone as a folder in My Computer. An external application which fetches data off the mobile phone in raw mode sounds more realistic.

So Mistrel does make a good point in his reply. Serial and COM devices are very complex and not simple. Why? COM is very modular. You can adapt a serial port to connect and do virtually everything you think is possible with computers.

Cheers, Irene.

> I might be able to help you, but I need to know EXACTLY which Samsung
> it is, which COM protocol the connection is used and which cable are you
> using

It's a Samsung SGH-E310, using a Samsung-branded serial cable made for
it with a model number of PCB093LBE. It says "Data Link Cable" and it's a
standard serial cable of 9 pins, connected through COM1 on my PC.

> can you tell that is the connection based on point-to-point access?

No idea.

> search on Google for "universal cell phone software"

Didn't see anything that could help.

Irene wrote:Yeah sure! Yeah, go on PB and download such software. Oh, but don't come back whining about it not working with your mobile phone and what I hate more than cold coffee are whining men ^.^

Sheesh, if that's the way you respond to other people trying to help, maybe you should "disappear" again....

PB wrote:Didn't see anything that could help.

Fair enough, it was just a suggestion since I didn't know what phone you had at the time I made it.

Not all phones will be supported and some can't be either because they don't have the ability or the system they use is entirely proprietary.

Before the company I work for upgraded me to a Black Berry, the phone I had was a Samsung and none of the universal phone software out there supported it. Though that may be simply because the phone didn't support it, even Samsung had no desktop software for it.