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Topic: USB Echo Demo on 18F2550 ? (Read 10071 times) previous topic - next topic

USB Echo Demo on 18F2550 ?

Gentlemen,

Just wondering what it takes to get the USB Echo Demo for 18F2550 up n' running?  I'm using a 20-MHz crystal so I modified the PLLDIV line, compiled, and programmed an 18F2550.  After I plug it into USB, Windows 7 Device Manager shows a device called "CDC Test" in "Other Devices" but it reports the following status;

Code: [Select]
The drivers for this device are not installed. (Code 28)

To find a driver for this device, click Update Driver.
I pressed the Update Driver button but Windows couldn't find a driver.

Did I miss a step?

Thanks in advance.

Cheerful regards, Mike

Re: USB Echo Demo on 18F2550 ?

Reply #1
probably .inf file..

try installing the drivers...you can download them from our svn
http://dangerous-prototypes-open-hardwa ... nf-driver/

do to device menager, find the offending device, and point the driver update to this .inf file..

Let us know how it went..
best regards FIlip.

Re: USB Echo Demo on 18F2550 ?

Reply #2
Hi FIlip:

A couple questions, please?

(1) Do I need to place those two files in any particular location, please?

(2) Is there a bootloader in that USB Echo Demo 18F2550 project?

Cheerful regards, Mike

Re: USB Echo Demo on 18F2550 ?

Reply #3
You can put the inf file in the dp_usb folder or anywhere else for that matter. The thing is you will need to remember where you put it and browse to it when you install the driver manually. Once the (windows in-built) CDC driver is installed then it is available for the usb port you installed it to. You will have to redo the installation if you change usb ports on the first time you change ports.

If you can, try to keep all the DP usb - cdc projects using the same usb port. This saves you from having to reinstall the driver each time a "new" usb is used and it also ensures that the comport number remains the same and saves the hassle of having to hunt around for it in device manager. It also prevents windows (XP at least) doing stupid things like getting confused about endpoints if say you try to run the HID test projects ( which are better run on a different usb port as far as windows goes, stupid windows, stupid!)

The cdc stack is the same for ALL DP projects so once it is set up for the first time any DP project using it can use the same usb port without further hassle.

There is no bootloader in the cdc demo projects as such however the (PIC18Fxx5x) code is compiled to leave space for the bootloader and ideally you should use the bootloader for the IR TOY and follow all the good directions that Ian has provided for installing and using the bootloader found under the IR TOY product wiki.

Re: USB Echo Demo on 18F2550 ?

Reply #4
Thank you JTR.  My board came up once and I was able to install the Windows driver and echo characters using a Terminal program.  It hasn't come up since then though.  Is there anything special about the 18F2550BB circuit I should know about (the schematic is missing from the PIC18F2550BB page)?  I do have a pull-up on MCLR and a cap on VUSB.  Basically, I'm replacing the 18F2550 in a PICKIT2 clone with another 18F2550 with the Echo Demo firmware.

Cheerful regards, Mike

Re: USB Echo Demo on 18F2550 ?

Reply #5
Is it possible there's some flaw in the USB stack in regards to operation on Windows 7?  I'm getting strange results.  For example, in order for the board to be recognized by Windows 7 I have to plug it into USB for a moment then quickly disconnect and reconnect to USB before it's recognized.  Weird, huh?

Re: USB Echo Demo on 18F2550 ?

Reply #6
I don't know of any problem with the usb stack and sindows 7 (Ok that was a typo but it sort of fits anyway...) Lat time I checked it all worked and there are no other reports that I know of saying otherwise.

On the face of it it seems that you have a reset problem on the pic due to slow Vdd rise or other cause. Try adding a reset switch to see what happens of you manually reset the pic, and/or try lowing the cap value on the USB rail.

Re: USB Echo Demo on 18F2550 ?

Reply #7
Ok, thanks.  So no reported problems with the 18F2550 Breakout Board, plus Windows 7, plus USB Echo Demo.  Is there anything special about the 18F2550 Breakout Board circuit (there's no schematic on the 18F2550BB page)?

I'll keep trying.

Cheerful regards, Mike

Re: USB Echo Demo on 18F2550 ?

Reply #8
[quote author="McLaren"]Ok, thanks.  So no reported problems with the 18F2550 Breakout Board, plus Windows 7, plus USB Echo Demo.  Is there anything special about the 18F2550 Breakout Board circuit (there's no schematic on the 18F2550BB page)?

I'll keep trying.

Cheerful regards, Mike[/quote]

sorry for the schematic.. you can find it in our svn
http://dangerous-prototypes-open-hardwa ... /hardware/

there is nothing special about the board, just USB..power supply, decoupelng caps, the oscilator circuit, UART proken out, and a power select jumper for USB/od DCIN power....

for the reset switch, you can just use a jumper wire over the MCLR and GND pins.....

so while keeping the board in reset plug it into the usb, and remove the reset...
best regards FIlip.

Re: USB Echo Demo on 18F2550 ?

Reply #9
Quote
So no reported problems with the 18F2550 Breakout Board, plus Windows 7, plus USB Echo Demo.

I tested and packaged it under windows 7 64bit, so it should work.
Got a question? Please ask in the forum for the fastest answers.

 

Re: USB Echo Demo on 18F2550 ?

Reply #10
Is there any signed driver? On Windows 7 it says "driver not signed"