One of my earliest "magic smoke" incidents came not long after I'd started work for BT. I accidentally shorted a lead on an 8080's clock generator chip with a scope probe. A strange device (bi-phase clock), it had both 12 and 5 volt supplies, and a chunk of the ceramic package took a lump out of my ear-lobe. I took to wearing safety glasses after that.
At my first PoW one of the EPROMs we used in development was affectionately known as the Bonanza chip - it'd been plugged in the wrong-way-round and got hot enough to burn the paper lable off of the window - It still worked fine, though
Oh, and this:
Stainless-steel hedgehogs: Project we were working on, but this wasn't us
We received this video from one of the other project engineers just after we'd had a phone call not to bother coming in to work that day as they weren't ready for us yet...
This is perfect timing. I was lecturing about subroutines on Tuesday and got a question about the maximum number of subroutines you could nest (i.e. what happens with the stack). I said that it could be unpredictable because, depending on the circumstances, you could be writing on-top-of memory that contains program instructions...
I'll be stealing this - and i'm going to scour Hack-A-Day for more stuff too. Thanks guys!
P.S. love the Bonanza clip. Not seen that in ages (although I used to hate it because Bonanza came on just after the cartoons finished - so it heralded the start of *boring* telly)
With my pleasure... BTW, did you get in touch with Mbed? Also, TMS32010 had only 4 words of "stack" of which you had to reserve one for the emulator (just incase your code didn't work straight out of the assembler ;)
We once had a very expensive image edge detector chip, issued on free-loan by a customer for incorporation into an image processing system. It came with a datasheet that said in big shouty lettering that under no circumstances was it to be taken out of reset without first fully initialising all its registers, otherwise it would go metastable, and melt itself. The customer made us all read this, and sign that we fully understood the consequences. We sweated bricks making sure the software was spot-on - fortunately, it all went well.
SOunds rather catch 22... you have to set the registers before brining it out of reset... whereas usually the first thing you ought to do is sanitize the registers, but how do you fiddle with registers *before* the first instruction - Sounds rather a "Big Bang" type problem....
One of my earliest "magic smoke" incidents came not long after I'd started work for BT.
ReplyDeleteI accidentally shorted a lead on an 8080's clock generator chip with a scope probe.
A strange device (bi-phase clock), it had both 12 and 5 volt supplies, and a chunk of the ceramic package took a lump out of my ear-lobe.
I took to wearing safety glasses after that.
At my first PoW one of the EPROMs we used in development was affectionately known as the Bonanza chip - it'd been plugged in the wrong-way-round and got hot enough to burn the paper lable off of the window - It still worked fine, though
ReplyDeleteOh, and this:
Stainless-steel hedgehogs: Project we were working on, but this wasn't us
We received this video from one of the other project engineers just after we'd had a phone call not to bother coming in to work that day as they weren't ready for us yet...
BRILLIANT!!
ReplyDeleteThis is perfect timing. I was lecturing about subroutines on Tuesday and got a question about the maximum number of subroutines you could nest (i.e. what happens with the stack). I said that it could be unpredictable because, depending on the circumstances, you could be writing on-top-of memory that contains program instructions...
I'll be stealing this - and i'm going to scour Hack-A-Day for more stuff too. Thanks guys!
P.S. love the Bonanza clip. Not seen that in ages (although I used to hate it because Bonanza came on just after the cartoons finished - so it heralded the start of *boring* telly)
ReplyDeleteWith my pleasure... BTW, did you get in touch with Mbed?
ReplyDeleteAlso, TMS32010 had only 4 words of "stack" of which you had to reserve one for the emulator (just incase your code didn't work straight out of the assembler ;)
We once had a very expensive image edge detector chip, issued on free-loan by a customer for incorporation into an image processing system.
ReplyDeleteIt came with a datasheet that said in big shouty lettering that under no circumstances was it to be taken out of reset without first fully initialising all its registers, otherwise it would go metastable, and melt itself.
The customer made us all read this, and sign that we fully understood the consequences.
We sweated bricks making sure the software was spot-on - fortunately, it all went well.
SOunds rather catch 22... you have to set the registers before brining it out of reset... whereas usually the first thing you ought to do is sanitize the registers, but how do you fiddle with registers *before* the first instruction - Sounds rather a "Big Bang" type problem....
ReplyDeleteImploding Vacuum tubes for science
ReplyDelete