what killed my PROP (was: Best way to End a Propeller (and how not to do it))
codeviper
Posts: 208
I was wanting to make a list of things that can end a propeller, i seem to have pigeon holed myself here like i somehow do everywhere.
i did not connect 9 volts to the prop and i have no shorts i went over everything twice to see why it died and there is no reason all i added to my prop was an SPI ram and an LED and infact i at the time did not have my SC card nor my PS2 keyboard attached.
here is my basic design
anyone want to tell me why this would break otherwise after i made sure the voltages were correct and my board is soldered? i have pins 16 to 24 available to use on a bread board but all the other pins are devoted to NES ports SD card TV composite I2C EEPROM and RTC and PS2 keyboard and two pins to a headphone jack. but i had nothing but the EEPROM TV and an SPI ram on pins 16 17 18 and 19 and an led on pin 20 when my PROP died. so why did it die on me? if it wasnt the adapter i used or the LED shorted to ground then what since everything else is permamently soldered in place and has worked for the past few months and hours of playing dodgey kong and defender and Xracer? oh lets not forget fantasy fighter
this is making me curious since everyone seems in conjunction that none of this should end a PROP and i have double checked every single wire trace and pin on my board all that is left is i got a bad PROP that just held in this long.
one funny thing i got 2 5MHZ crystals and my oscilloscope and multimeter bothe aggree they are only 100 to 200 HZ off at most but ALL programs i run on the prop needs to be adjusted by 2KHZ? if i don't adjust the picture is only black and white. is it cause my PROP realy was bad?
this sucks big time for me since i had just got a little time to actually get going on my propeller projects.
I want to compile a list of THE WORST THINGS TO DO A PROPELLER
and have it for all newbies to see.
it will be ordered from most likely to end the prop to least likely.
i may have ended my own PROP so i decided to do this if you have any anecdotes or stories of how you brought an end to your prop lets here it.
if you got any good "don't do this, do do this" advice lets here it to.
the main reason i bought the prop was the Temp test video i thought well if it can handle that maybe it can handle me
my thing is i may have had to much amprage on my AC adaptor 9 volt 1.2 amp, or it was that i pluged pin 20 into an led then the led to ground without a 240 ohm resistor. why? well my phone rang and i forgot what i was doing thats why lol. anyway my board isnt working now but the chip is still getting 3.28 volt and i am lost as to why its not working.
i did not connect 9 volts to the prop and i have no shorts i went over everything twice to see why it died and there is no reason all i added to my prop was an SPI ram and an LED and infact i at the time did not have my SC card nor my PS2 keyboard attached.
here is my basic design
anyone want to tell me why this would break otherwise after i made sure the voltages were correct and my board is soldered? i have pins 16 to 24 available to use on a bread board but all the other pins are devoted to NES ports SD card TV composite I2C EEPROM and RTC and PS2 keyboard and two pins to a headphone jack. but i had nothing but the EEPROM TV and an SPI ram on pins 16 17 18 and 19 and an led on pin 20 when my PROP died. so why did it die on me? if it wasnt the adapter i used or the LED shorted to ground then what since everything else is permamently soldered in place and has worked for the past few months and hours of playing dodgey kong and defender and Xracer? oh lets not forget fantasy fighter
this is making me curious since everyone seems in conjunction that none of this should end a PROP and i have double checked every single wire trace and pin on my board all that is left is i got a bad PROP that just held in this long.
one funny thing i got 2 5MHZ crystals and my oscilloscope and multimeter bothe aggree they are only 100 to 200 HZ off at most but ALL programs i run on the prop needs to be adjusted by 2KHZ? if i don't adjust the picture is only black and white. is it cause my PROP realy was bad?
this sucks big time for me since i had just got a little time to actually get going on my propeller projects.
I want to compile a list of THE WORST THINGS TO DO A PROPELLER
and have it for all newbies to see.
it will be ordered from most likely to end the prop to least likely.
i may have ended my own PROP so i decided to do this if you have any anecdotes or stories of how you brought an end to your prop lets here it.
if you got any good "don't do this, do do this" advice lets here it to.
the main reason i bought the prop was the Temp test video i thought well if it can handle that maybe it can handle me
my thing is i may have had to much amprage on my AC adaptor 9 volt 1.2 amp, or it was that i pluged pin 20 into an led then the led to ground without a 240 ohm resistor. why? well my phone rang and i forgot what i was doing thats why lol. anyway my board isnt working now but the chip is still getting 3.28 volt and i am lost as to why its not working.
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Comments
The adapter amperage, no matter how high it is, cannot damage the Propeller or any circuitry it is connected to for that matter. The reason is that the adapter does not push the current, it provides the current. So if your circuit consumes 20mA, and you use a 10A adapter to power it, your circuit will only pull 10mA.
but serious anyone else have a prop die?
thanks lardom that was exactly the kind of thing id like to hear new users can understand that
those technical measures don't always click to new people and hearing here is what i did and what it did realy clicks with new people.
my whole ideal is to promote new electronics hobyists into the amazing world of DIY digital electronics.
BTW a circuit can allow a push of high amperage, if i was wrong surges would never ruin appliances and no human would get a deathly shock from an outlet.
i have a 5v regulator going into a 3.3volt regulator for the prop. the 5 volt can handle up to 15 volt in and can handle 1amp draw and is supposed to have thermal and short protection and the only other thing connected to the prop was the 3 resistor DAC for TV composite video and the LED and a SPI sram
anyone got a good reason a prop would die other then the AC adaptor being a high amperage/or bad or the fact i had put the led from pin to ground and forgot the resistor (yes i know i know but you try and remember to put in a resistor when your mom call and says " my car broke down, i need help) i came back home put the power on the PROP worked a while then nothing.
That is why if your circuit draws say, 100mA in normal operation, it doesn't matter if the supply can provide 150mA or 150A. Your circuit equivalent resistance doesn't change, so your circuit will only pull 100mA from the supply. But if you should happen to short something, the fireworks will be much bigger with a supply capable of 150A!
I think I have killed one Prop out of the ten or so I have used, with that failure down to 9V being where it oughtn't to be. In the same period, whilst subject to the same level of ill-informed tinkering, experimentation, errors and omissions, quite a few sensor boards, accessories and displays (of various provenance and vendors) have given up the ghost (not, I hasten to add due to any fault of the Prop to which they were connected).
The Prop seems remarkably tolerant to my 'I wonder if that'll connect there ... Oops! Maybe not! Ooh, it still works!" development cycle.
The protoboards I own that have ended their life have done so because they have been re-purposed so many times that they are too splattered with gash soldering and too littered with dead pieces of wire for me to summon up the enthusiasm to sort them out in order to start anew: in every case the the Prop chip has been fine.
I wouldn't be too surprised if they found a Prop protoboard working at the bottom of one of the super-thermal vents that were thought to be toxic to all life.
The noblest way for a prop to go would be valiantly commanding a (losing) robot in "Robot Wars" or piloting a quad-copter in a thunderstorm(!)
The Prop was very hot (I think the regulator resistor was wrong as well come to think of it). Anyway, I waited for the chip to cool down enough that I could touch it and then fixed the resistor and the wiring issue. Turned it on again and it worked fine. I'm still using that same chip a year later in the same dev board.
So yeah, as already mentioned the Propeller is pretty damn resilient and noob proof. I've never managed to kill one yet... op amps on the other hand, I seem to have the touch of death when they are involved.
The "Robot Wars" death of a prop might just happen if I get back into that. Though the brains tended to be the most protected parts of my bots.
Lawson
i am ordering new parts and want you to know i am adding a set of buffer transivers to protect the prop they are 74HCT so they can handle converting 3.3 to 5 volt circuits ( i hope ) yes it was my connected that flippin led with no resistor such a bone head move yes i know. i am also adding a serial to parallel and parallel to serial chips to give me 8 inputs and 8 outputs for 4 pins data in data out shared clock and enables. plus since they are 74CHT chips i can interface them to % volt chips and power them off 3.3volts
but yeah anything on this topic is cool including the things that DID NOT kill the prop.
you see the big sell for me was the paralax test on youtube where they flippin BAKE the prop. i said well if it can survive that maybe it will run for me at least a while.
i went and got a quickstart board, i like it, but i am saving it for something special.
1) Connect it backwards ((-) to Vdd and (+) to Vss)
2) Connect a source of power to the chip's power connections at any voltage in excess of the Absolute Maximum rating of the chip (something like 4V for 3.3V parts and 7V for 5V parts ... the datasheet usually gives a value). They're not called Absolute Maximum ratings for nothing.
In addition, you can generally blow a specific pin by connecting it to a source of voltage greater than Vdd+0.6V or less than -0.6V. The Propeller seems to be fairly resistant though to too much current from an I/O pin.
Thanks a VIP
But is shorting a output to ground gonna fry it?
I am pretty sure what ended mine was connecting a pin to and led then that led to ground and having the led switch on and off.
It makes me think that scenario is unlikely.
it has 3.3v a good ground nothing was connected save for one SPI ram and a TV set and the LED when it stopped.
so i only started this in the assumption that I DID IT and to tell others DONT DO THIS
but as you guys go on it seems like my PROP just died on me which sucks can i get it replaced then cause if i didn't do it and the PROP is so tough then that means mine is faulty.
kinda funny the interesting thing is if people didn't want to say I was wrong it wasn't my power supply and its not my LED mistake i would have just assumed it was me and left it be.
I have 10 65c02 CPUs from the 80s and been using them for more then 15 years, none of them died on me.
my crystal is 5Mhz
and this is my board except i used the DIP not the SMD chip
anyone want to give me a reason it failed great otherwise i want a new chip
I am just working on getting really going all the stuff i have done till know was MOD the other code thats been posted to run on my board wich now has an SD card slot and NESports and I use a KYDOS cut down to just use the keyboard and a TV and my board has an LCD from a DVD player and runs off of 6 NICAD AAs VIA the REGULATORS of course.
so when it died the SD card WAS NOT IN and i was powering it off a 9volt 1.2 amp AC adapter not my batteries and only a TV was connected to it.
sorry if this seems grouchy or mean, its just as a full time student losing $9 to replace i chip is bugging me and now it seems like im being told it should not have went normally under these circumstances. hence making this not my fault, which bugs me more.
what you don't know you know,
what you know you don't know
and
what you don't know you don't know.
But there is no way someone else can tell you what you don't know...
For all anybody knows, it may have been the carpet...
Yours schematics don't show if You have decoupling capacitors around PROPELLER same is shows only 10uF capacitors around V-Regulators but not 100nF ones that are needed to.
Capacitors around Propeller will have 100nF to. And all IC's You use need that 100nF decoupling capacitors to.
thank you that is a great suggestion. but that schematic is from the Propeller demoboard i just took out the VGA microphone mouse and audio circuits. if it is wrong then parallax is wrong which makes me flipping happy as a jaybird, tweet tweet
so when will i get a new propeller chip?
i just followed instructions.
if needed i could send in my board for parallax to look over.
i do not think I would get a replacement chip but it is funny how many though id seriously put 9 volts on the propeller.
About Amps just to check up on it a talked to some college professors on surges and amperage.
here is the general answer.
"yes a surge of current can occur in certain situations, like when a high drain device is suddenly disconnected or a power source is in a questionable condition."
i asked can you give an example?
the answer from one was
"a blackout for instance will often be an isolated spot that is disconnected from the grid through one thing or another, and then the current that was being drawn from that area surges to surrounding areas of the grid"
the other told me something about idustrial controlls at a factory and the bulbs blowing over head as all the robots shut down suddenly due to a computer failure. but his story was so long and detailed i went to sleep.
to test this i wired a 5 volt regulator that was rated to take 16 volts to a car battery wich is only 12 volts the regulater promptly smoked! not saying that THIS IS what killed my PROP I am just saying that Amperage can surge over a circuit and cause damage and proper care over AMPs does mater.