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Topic: "Device not found" (Read 2520 times) previous topic - next topic

"Device not found"

Hi...

I completed a new build of a Logic Sniffer and programmed PIC and FPGA ROM successfully (trying all v2.0 ROM files as well).  At this point, I can enter program mode successfully and read status without an issue.  Once reset, ACT LED flashes several times and then goes out which should signify that FPGA was programmed correctly (?)  Once I open OB_LogicSniffer.exe I get a "Device not found" error which I can't get past.  I've tried multiple computers, no USB hubs, etc. and nothing changes.  The " selected transfer rate warning" that is included with the error (connected to specified port, turned on/properly programmed, set to selected transfer rate) makes me wonder if that's what I'm missing.  I've tried adjusting COM port speed settings to 115200, programming ROM with -t:115200 option and nothing works.  Am I missing a step?  I've verified the COM port, but can't get the client to connect to the LS board.  Any ideas?

Thanks!

Re: "Device not found"

Reply #1 –
There is a problem with the BP_LogicAnalyzer.exe code and the time-outs used.  I put a serial-port monitor in and found that the unit is responding, but I still get the "Device not found" error.  If I interact with the unit using only the serial ports, everything works fine.  I saw another post mentioning that they need to set the time-outs from 100ms to 500ms, but you have to get source-code to do that.

I've found that occasionally mine will work, you have to unplug it, wait, replug then it will sometimes work.  Once if fails, forget it, you have to unplug again.

I was considering writing my own interface program in C#, but I really do not have the time just now.

-Matt

Re: "Device not found"

Reply #2 –
I agree with TheMattster. Your problem seems to be the same as reported by otheres and is addressed
in more detail in the ***Possible solution to intermittent communication problems*** thread

Loading of the FPGA configuration image from SPI flash into the FPGA upon startup seems to work
on your board (as the blue LED stops flashing a few seconds after powering on your OLS).

A simple test of the communication between the PIC and the FPGA (to see if the PIC can talk to
the FPGA at all) would be to connect to the OLS with the Hercules Utility and to send the ID
request command (02h). If the connection between PIC and FPGA works you will receive four
characters starting with "SLA", followed by a number (protocol version). It will be interesting
to see if you can open the serial connection and then perform the simple ID request test.

Re: "Device not found"

Reply #3 –
The ***Possible solution to intermittent communication problems*** thread (http://dangerousprototypes.com/forum/index.php?topic=549.0) has a post from robots that fixes the problem!!!

[glow=red,2,300]THANK YOU robots!!![/glow]

-Matt

Re: "Device not found"

Reply #4 –
I added this to thread  549 concerning intermittent problems http://dangerousprototypes.com/forum/in ... opic=549.0
but it seems more appropriate here:
I have two OLS, one works in the OSX or XP the other always fails with "device not found"
I have tried the analyser.jar with the delay file from the 19th May as well as altering the advanced port settings, with no joy.

FYI, all LED appear to provide the correct feedback, making the assumption that all is good.
 It is recognised in the device manager ports, I can upload different bit streams to it, but as soon as i hit 'capture' the device not found' rears its ugly head.

I would now assume that this is not software based but hardware based issue we have here as one OLS functions faultlessly and the 2nd doesn't?

Using realterm as  an interface, when sending "02H" I get feedback with the working OLS, the other OLS (that gives "device not found" with sump) offers me nothing (empty display)

How can I tell if the PIC is working properly?

Re: "Device not found"

Reply #5 –
swissMac, what you describe is not surprising at all after the cause of the "intermittent communication problems" has been established within the UART part of the SUMP VHDL code ... it affects only a number of FPGA chips while others work perfectly fine or show the problem only sporadic/randomly. The explanation why certain chips are not affected while others are more or less affected lies within the (specified) electrical tolerances of the FPGA chips (even those chips that show the problem must be considered good). It explains why one of your OLSs just works fine while the other fails always.

Essentially the UART part in the affected FPGAs will not interpret the characters it receives from the PIC correctly. Therefore the SUMP engine will not receive the command (properly) and will not repsond when you send 02h.

It is the PIC that enumerates as a USB device and establishes a virtual COM port connection (but only between PC and PIC) so you see the COM port in the device manager but since the communication between the PIC and the FPGA fails, the Java client can't establish a connection with the SUMP engine (FPGA) and displays the "Device not found" error when you try to start a capture even if you have selected the correct COM port.

This problem will be solved soon by a new bitstream.

Re: "Device not found"

Reply #6 –
Hi swissMac - I think you're encountering the intermittent com problem too, it sounds like the same thing I'm finding here:
http://dangerousprototypes.com/forum/in ... opic=518.0

We should have some major updates this week.
Got a question? Please ask in the forum for the fastest answers.

Re: "Device not found"

Reply #7 –
Many thanks IPenguin and Ian for the feedback and the explanation.

Looking forward to try the new bitstream
The real shame is the weather turned nice .......... :-(