NXTrfs (remote filesystem)

[chrimo]

Hi all,

is there anybody out there, who needs nearly unlimited disk space for the NXT ?

My first idea was a hardware solution:
NXT-->RS485-->ATMegaMCU-->SPI-->SD-Card (up to 2 GB cheap flash space + DOS filesystem)

But this project is currently pending because due time...

Now I'm trying the following idea:
using filesystem from foreign devices (remote filesystem).
e.g. diskspace from notebooks or mobile devices running a small JAVA listener service.
The NXT should be able to connect to this devices via bluetooth, rs485 or I2C.

Samples:
NXT-->BT-->WindowsMobile+SD-Card
NXT-->BT-->PC

What we need is:

1. NXT part of the filesystem driver
2. PC part of the filsystem listener (like a fileservice)
3. common protocol specification (e.g remote_open(),remote_close(), remote_read(), remote_seek(), remote_write(),...)

Suggestions ?

Christian

[gloomyandy]

Out of interest why do you need a large amount of file space? How do you plan to use it? I ask because often it is easier to implement a specific service (say data logging), rather than a generic one (like file system access)....

Andy

BTW Are you really planning on talking to a PC via i2c?

[chrimo]

Hi,

I2C or any cable connections are very stupid but the solution should be transport independant Using my phones sd-card makes much more sense...
A transparent filesystem access layer will be very flexible and will work with every application.
I'm thinking about using maps for navigation or sound files to play...

A client server application with special services will be enough for the first step, but the rfs like nfs will be the king of my dreams...

1. syslog like client
application-->logger class (log4java)-->BT-->jproxy-->syslogd

2. ftp like client
application<-->ftclient class<--BT-->jftproxy<-->Filesystem

Just to say it in my own poor words:
Humans are using NXT-Browsers,
robots need similar access to remote diskspace or filesystems.

Real intelligent autonomous robots need more space than <256kB

Just some brainstorming
Christian

[chrimo]

I forgot to mention:

why not use the Lego Communication Protocol (LCP) access to the remote device with storage ?
The advantage could be the existance of many usable classes

Just do it the reverse direction...

Christian

[bbagnall]

That sounds like a good idea. I had dreams of implementing OBEX in leJOS NXJ but unfortunately the Bluecore chip in the NXT brick is limited and doesn't allow the NXT to advertise those services. The advantage of OBEX is that we wouldn't need any special software running on the PC side.

But there is nothing stopping us from making our own proprietary service. It's just not as convenient because the user would need to run a small application on the PC to make it work.