G400D Basic Questions

I am wondering about a few things on this G400D.

  1. Looking at the products page for G400, it is talking about loading Bootloader
    version 2. My question: Do I need to worry about this? Wouldn’t it ship preloaded?

  2. I have the FEZ Config program which I"ve used on both Spider and Cobra devices, can
    I use this on the G400 or do I need to use the new Tiny Clr Loader?

  3. I do have a G400D and for now, I’m unable to see anything in my computer’s device manager when I connect to the usb debug port (hence the questions above).

If I do have to load the bootloader, it seems like it will be difficult for me to connect spi1miso to ground…Is there a testpoint or something to make this easy?
Just trying to get started…


What board do you have this plugged into? Custom or G400D dev board?

How do you have USB connected?

You can re-use your code for the Cobra by changing the GPIO ports if you used them and everything should still work. You can’t load the Cobra or Spider BINARY you created. You need to recompile from the source.

FezConfig works with the G400D. I have not switched to TinyCLR on the G400D and still use NETFM 4.3 as currently there is no GUI support in TinyCLR.

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I think this is the fundamental issue you need to resolve before you attempt anything else. As @Dave asks:

this will be key. If nothing is showing up, that’s not an issue with bootloaders or firmware, that’s fundamental USB connectivity.

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You first need to determine if you are using NETMF or TinyCLR. Then you can decide on what to miss and what the appropriate steps are.

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Thanks for your response -
I have a custom board plugged in but I didn’t create the board.
I’m not exactly sure how the usb is connected other than it is a micro usb connector.
There are two of them and I see that one does connect as a USB Serial Port (COM14) on
my computer, however, I don’t think it is the correct one to use as the debug usb connection.
(I did try to use this from FEZ Config but doesn’t work, as I tried to ping it as a serial Port 14 but
says Failure - Device is not connected or not responding).
I did not know TinyCLR has no gui support so this means I will have to stay with NETFM 4.3.
good to know this info - thanks!

Ok, thanks for the response, I guess I was confused by the documentation (g400.html) Loading Bootloader
Version 2 instructions step 5. and step 6. seemed to imply after going through the bootloader installer and connecting
the spi1_miso pin to ground, wait 3 seconds, remove connection then I would see a COM port in the device manager.

I guess I need to retrace with the guy who created the custom board what was done. maybe I’ll also order a G400 development board just to see if the G400 debug port is working with that. might be good to have that dev board to
help with possible future problems anyway…


thanks - I guess I now know I should stay with NETMF based on what I learned from these replies.

Are you sure you have winusb installed.

I ask because I do not know what PC OS you are using.

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Thanks for responding willgeorge.

I am running windows 7 32bit and am able to connect debug with older devices such as Cobra and Spider.
But, I double checked anyway and could see that I do have winusb.sys in the path shown in your post.

thanks again for your help.

drivers won’t matter. If the device doesn’t show up in Device Manager, there’s a fundamental issue that the USB device doesn’t appear to the USB bus even before it gets presented to the OS. If there’s no matching driver, it’ll just appear with an exclamation mark. This is one reason I turn sound on and listen to the connection sounds - if you get no noise, it’s not even getting power from the bus; if you get a high-low noise you are taking power but not presenting a device, and if you end up with a low-high noise you are presenting a USB device to the OS. You might get repeated high-low which can be signs a device is trying to draw too much power or has a short. All great additional diagnostics

Sure. When things work, this will happen - but if you don’t try to get into bootloader mode it should also appear as a device, and it’s unlikely getting into bootloader mode will get you any further if you have a USB connection issue in the first place.

hope these additional steps help, at least they may help show your next area of focus (and until your devboard arrives :slight_smile: )

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FYI - Just wanted to let you all know this item can be closed.
I got the eval board today and the G400 I had works ok with it (as far as connecting usb debug).

So, I can go back to the guy who made the custom board and prove it is something with his board.
Thanks again!!