Help needed to select board for my project prototype

I am new to NETMF & Gadgeteer.

My task is to develop a reliable device that works in a fairly decent industrial environment.
Such a device would wait for USB memory stick to be plugged in it.
Once a USB memory stick is detected, this device queries another MCU over RS232.
Replies from that MCU over RS232 shall be consolidated and stored as ascii file on the USB memory stick.
USB memory stick will ofcourse be formated in FAT32 file system.

So my need is a reliable board with USB host and RS232 port. And ofcourse a USB client port for program download / debug.

I have narrowed down on FEZ Reaper Mainboard + RS232 module.
Please suggest me a reliable ubs client + power module.

Also, is there any limitation on capacity (size) of USB memory stick when using this configuration ?

Please advice.

@ aavinan - Any of the USB Client modules will work fine for you:

The maximum supported file size is 4GB in FAT32, though I do not believe that we impose any limits on the size of the USB memory stick itself.

@ John -

USB Host supports 1.1 or 2.0 ? There is no mention in the specsheet.

Also, do i need to buy SD card module for program memory ?
My application is very small. So will the built-in user flash will do for it ?

My project volume is small. So i shall go for reaper mainboard for production.
Is reaper mainboard suitable for industrial environment ? Any EMI/EMC test done on it ?

@ aavinan

[quote]Also, do i need to buy SD card module for program memory ?
My application is very small. So will the built-in user flash will do for it ?[/quote]

The built-in flash will be sufficient.

There are limitations on the size of a MF assembly, and with large programs you might have to split the program in multiple DLLs. I have never heard of anyone who had a problem with insufficient user flash.

USB 1.1 “Fast USB”

Thanks. Please suggest any board with soc that supports USB 2.0?

I think all the SoM and SoC that GHI offers have USB 2.0 Host / Device / OTG (at least the Cortex chips). However I am not sure how the drivers operate.

@ aavinan - Our boards only support full speed USB.

ALFAT supports accessing USB files in high speed. Internal speed is about 4MB/sec.

@ Gus - Speed is not problem here, as the data file size is only around 10kb. Only concerned about the backwards compatibility of USB3.0 usb flash drives. After installation, i don’t want to encounter compatibility issues with latest USB sticks.

Has any one experience such USB stick backwards compatibility issues ?
Still, i would order a sample unit and see that myself.

Gus, would any one help me double check my cart ?


All our devices are 2.0 compliant and all 3.0 devices should be backward compatible with 2.0.

I do not see why there would be any concerns.

@ Gus - Fine. Ordering sample boards :slight_smile:

BOM :-
FEZ Repear Main Board
RS232 module
USB Host module
USB Client DP module

Am i good to go ?

USB host is supported but no hub support on G80, unless the team added this in latest release? It maybe fine for you but I would go with the FEZ Spider for start and then switch to Reaper in the future… actually, you should order both :slight_smile:

@ Gus - Also added Spider along with J11D module. Ordered just now.

Thanks guys, for your time.

For your concern on the USB speed versions there is not much to think of. Backward compatibility with older USB devices would not be a problem. The latest USB 3.0 will only run slower and the full speed capability of it would not be utilized. But since you only need 10kb for the data file size you would not even notice the speed difference.

circuit board assembly