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Topic: BusBlaster not working (Read 5154 times) previous topic - next topic

BusBlaster not working

Hi, I purchased a bus blaster a while back but never got a chance to use it, when I try now it says TDO stuck at 1 when connected and TDO stuck on 0 when there are no connections. I have read through this forum, on ways to solve this issue but non seems to work.
Its a version 2.5 and I have been at this for just over a month now. Any Ideas will be welcomed.

Thank much kyron

Re: BusBlaster not working

Reply #1 –
Hi kyron, welcome to the forum!

[quote author="kyron"]...when I try now it says TDO stuck at 1 when connected and TDO stuck on 0 when there are no connections. [/quote]
Hmm, when it is connected to a circuit, right? When there are no connections it is normal to have a TDO stuck at 0 error. It is trying to see if there are some problems with the JTAG chain when programming so TDO stuck at 0 means there is an open circuit on the chain (or path shorted to GND) and TDO stuck at 1 means the chain is shorted to Vcc or parts are defective. If you are connecting TDO to a signal that never changes and near Vcc, that error may be possible.

If you want to test it out, there is a test bitstream and test program (windows only :( ), check out Ian's message on another topic.

Re: BusBlaster not working

Reply #2 –
Hi,
Some more infos might help to debug this.

Which OS?
Which clientsoftware (guess URJTAG, but which version)?
Which drivers (question might be redundant if OS==Windows)?

What you could try is to connect to the CPLD on-board. The serial-jtag chip on board has two channels. One is connected to the JTAG interface of the CPLD to be able to upgrade the firmware.  You can select the port via urjtag by
urjtag> cable jtagkey interface=[0,1]

Other then this, I kind of remember that this problem appears to happen with the open source ftdi drivers under Linux (this are the drivers which came with the kernel in most of the cases).
I figured out that I could get around it by explicitly refer to the cable address.
I will describe that method if you need it.

Re: BusBlaster not working

Reply #3 –
Hi, it windows OS, Urjtag 10, even tried openOCD with no luck. Can't talk to the CPLD.

Do you guys know when the bus blaster version 4.1 will be available for purchase?

Re: BusBlaster not working

Reply #4 –
[quote author="kyron"]Hi, it windows OS, Urjtag 10, even tried openOCD with no luck. Can't talk to the CPLD.[/quote]
So I believe you tried using the test procedure? With urTAG, I believe you tried both interface=0 (normal usage, not needed actually) and interface=1 (for on board CPLD).

[quote author="kyron"]Do you guys know when the bus blaster version 4.1 will be available for purchase?[/quote]
It is a future project, it'll probably take a while to mature.

Re: BusBlaster not working

Reply #5 –
Hi,

kyron, to help you.... help us ;)
Please show exactly what you did and what you typed in. It could be a very small point which makes all goes wrong and we can´t really help you with just more wild speculations.
E.g. Make a plain copy of what your tried to connect to the on-board CPLD, including all messages received from the terminal.  If its too long and boring paste in somewhere like pastebin (make sure its valid forever, so people in a year or so who are looking for the same problem can still find it) and send a link here... or copy it in a plain text file and attach that.

Re: BusBlaster not working

Reply #6 –
Hi,

Thank you all for your help, I have successfully destroyed my Bus Blaster. I tried to reflow the solder to the pins and it shorted the FTDI chip when I plugged it in, plus I damaged the PCB in the process.

Re: BusBlaster not working

Reply #7 –
Sorry to hear about the destroyed board, I'm 99% certain it was not a hardware problem that could be solved by reflow.

For anyone else contemplating this, here's two things to check:

First:
Quote
when I try now it says TDO stuck at 1 when connected and TDO stuck on 0 when there are no connections.

This means the hardware is likely working correctly. A stuck value that NEVER changes is more likely to be hardware issues.

Second, always try the self-test. It will let you know if every pin is toggling like it should:
viewtopic.php?f=37&t=4754#p46044

Third bonus pleading from Ian:
Quote
Please show exactly what you did and what you typed in. It could be a very small point which makes all goes wrong and we can´t really help you with just more wild speculations.

Seeing exactly what was attempted is the only way to help diagnose issues. Please always post screenshots, command output, config files, whatever you've been trying.

@kyron - I'll still replace this Bus Blaster. Please contact seeed with your order number and reference this thread.
Got a question? Please ask in the forum for the fastest answers.

Re: BusBlaster not working

Reply #8 –
Hey Ian,

Thanks muck for your assistance, I deeply appreciate it and to everyone that helped with there useful comments.

Thanks again!