Mark Rogers wrote:
The application I am playing with primarily involves shuffling data from a serial port (via a USB to RS232 or 485 converter) to a remote server over a VPN. So I need the box to be able to establish a VPN connection on startup (and re-establish it if it drops), and to allow me to run some simple scripts to link data coming to/from the server to the USB serial port. Biggest issue I might have would be the USB/Serial - what chance of getting drivers to work?
What script languages are already available as binaries that run on the box? Python, Perl, PHP, etc? (I'll probably need to put a web interface on the box as well but I know it can do that.)
I honestly have no idea how much of what I know I could do in Linux on an Intel platform is transferable to the ARM in practice. I know binaries won't work but I don't know how easily applications will cross-compile in practice.
I've done something similar to your serial project on the foxboard from acmesystems (that uses an axis etrax cpu rather than an arm) In my case it was making a serial diagnostics port available over GPRS. I found the few bits of software I needed were trivial to recompile for the etrax so should present no problem on an ARM
As Mick said. ARM is a well supported arch on Debian and in fact I think it is a requirement for debian stable packages that they are available for all supported architectures. Things like kernel modules for usb-serial converters should be also straightforward as ARM is a well supported kernel target so the only things that would give you trouble is stuff that relies on some binary blob that isn't just firmware (like say the nvidia drivers)
One thing I did which I think is quite a handy thing to do is I built my development environment for the Fox inside a virtual machine. That way if you need to hand off the project later on you can easily supply the compete toolchain used for building the system without worry that it is missing some critical dependency.
One thing you also need to watch is that some serial devices have problems with the inherent latency introduced with a USB-serial converter. So I would try a direct connection to the device via such a converter first before deciding on a platform that doesn't have real serial ports available.