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BF533 ICE question

Started by Andre Lodwig October 9, 2007
Hi all,

I have designed a board containing the BF533 blackfin, silicon 0.4, and 
try to get it running using the USB ICE from ADI with VisualDSP 4.5.

I used a small "blink_led" example as a basis.

The processor starts, but hangs within the "basiccrt" code, producing an 
"unknown exception" when executing an RTI to switch to user mode.

What could I have done wrong on my PCB here?
Voltages look OK, Xtal runs at 25MHz.
EMI design should not be too bad, ICE connections are less than one 
inch. SDRAM and FLASH are not used or even initialized at that stage.

Best regards,

Andre

Andre Lodwig wrote:

> Hi all, > > I have designed a board containing the BF533 blackfin, silicon 0.4, and > try to get it running using the USB ICE from ADI with VisualDSP 4.5. > > I used a small "blink_led" example as a basis. > > The processor starts, but hangs within the "basiccrt" code, producing an > "unknown exception" when executing an RTI to switch to user mode. > > What could I have done wrong on my PCB here?
If the ICE works at all, then there is nothing wrong with the hardware. Most likely there is an error in the project configuration. The VDSP has the hideous linker files with the size of 30k or so. The best thing to do is to scrap it and make your own. Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
Hi all again,

I have found my problem: when migrating from the BF536 to the BF533, I 
did not notice that the polarity of the NMI is inverted. So, my NMI is 
active all the time.

Next question: Is there any hack to disable the NMI via software? The 
pin of the BGA is unreacheable...

Best regards,

Andre


Vladimir Vassilevsky wrote:
> > > Andre Lodwig wrote: > >> Hi all, >> >> I have designed a board containing the BF533 blackfin, silicon 0.4, >> and try to get it running using the USB ICE from ADI with VisualDSP 4.5. >> >> I used a small "blink_led" example as a basis. >> >> The processor starts, but hangs within the "basiccrt" code, producing >> an "unknown exception" when executing an RTI to switch to user mode. >> >> What could I have done wrong on my PCB here? > > If the ICE works at all, then there is nothing wrong with the hardware. > Most likely there is an error in the project configuration. The VDSP has > the hideous linker files with the size of 30k or so. The best thing to > do is to scrap it and make your own. > > Vladimir Vassilevsky > DSP and Mixed Signal Design Consultant > http://www.abvolt.com
"Andre Lodwig" <a.lodwig@lrz.tum.de> wrote in message
news:fehuu0$5o3$1@news.lrz-muenchen.de...
> Hi all again, > > I have found my problem: when migrating from the BF536 to the BF533, I > did not notice that the polarity of the NMI is inverted. So, my NMI is > active all the time. > > Next question: Is there any hack to disable the NMI via software?
Not really. Although you can hack the C startup to make the code execute from the NMI context, that will block all of the other interrupts. At least you can do some hardware testing.
> The pin of the BGA is unreacheable...
Well, it is quite possible to rework the BGA and tie the NMI to GND. Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
Hi Vladimir,

thanks for the hints. I have tried to cut the ball by pulling a electric 
guitar string through them and "cut" the balls. Fortunately, the ball in 
front of the one I want to cut is the RTC supply, which I don't need.

I think I have tied the ball to ground now, by putting a small piece of 
metal and a small ribbon from overhead transparent under the chip. The 
NMI now shows up as inactive in the VDSP.

I have 5 boards to modify, so this will give me some hours of work to do 
the other 4.

BTW, I had tried to buzz the wire before, by applying 1V 3A from a power 
supply, but the trace withstood 3A with no problem.

I now have the effect that the disassembly window is missing in VDSP 
4.5, but this seems to be a software issue.

Best regards,

Andre


Vladimir Vassilevsky wrote:
> "Andre Lodwig" <a.lodwig@lrz.tum.de> wrote in message > news:fehuu0$5o3$1@news.lrz-muenchen.de... >> Hi all again, >> >> I have found my problem: when migrating from the BF536 to the BF533, I >> did not notice that the polarity of the NMI is inverted. So, my NMI is >> active all the time. >> >> Next question: Is there any hack to disable the NMI via software? > > Not really. Although you can hack the C startup to make the code execute > from the NMI context, that will block all of the other interrupts. At least > you can do some hardware testing. > >> The pin of the BGA is unreacheable... > > Well, it is quite possible to rework the BGA and tie the NMI to GND. > > > Vladimir Vassilevsky > DSP and Mixed Signal Design Consultant > http://www.abvolt.com > >
Andre Lodwig wrote:
> I now have the effect that the disassembly window is missing in VDSP > 4.5, but this seems to be a software issue. >
You can get that back by going to View->Debug Windows->Disassembly -- Jim Thomas Principal Applications Engineer Bittware, Inc jthomas@bittware.com http://www.bittware.com (603) 226-0404 x536 People think it must be fun to be a super genius, but they don't realize how hard it is to put up with all the idiots in the world - Calvin