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softcon
12-12-2011, 05:50 PM
Can someone help out here?
I purchased (with my last order) a super carrier board (I think that's what it's called) item number 700-32305.
The regular bread board type wafers are no problem, I'm using those in 3 different projects. However, my attempt to use one of the tall two-row pieces (four are included in the pack) met with disaster. I had thought that the four groups of 6-pin sections were built with the ppairs of holes being electrically connected (since if you hold it on end, there's two rows of six pins in each group) Perfect for plugging a chip into one side, and wires for connecting to other parts on the other side).
Unfortunately, either I wired things wrong, or this isn't the case.
I managed to toast my bs2 homework board by trying to do this with the 2x16 lcd module. I had the display plugged into the bs2 breadboard, and it worked fine, but I was attempting to clear space on the bs2 board, so tried plugging it into one of these thinner 2-row parts instead (after sticking it on front of the bs2 in front of where the battery goes) this would allow me to run the display away from the board, and still give it support with some other sort of setup.
Anyway, what I got instead was a very hot battery, and a no longer operational bs2 board. Although it still allows me to download programs to it, it no longer runs code so downloaded. My attempts to blink leds does nothing, except leave the leds on all the time <sigh>
I'm assuming this is because I cross-linked power with pins that weren't meant to carry the power, so can anyone verify how these thinner breadboards are supposed to be used?
Is it that the groups of six are electrically connected, or the groups of two (depending on how you hold the thing)

Thanks for any assistance. I'll definitely not be using those again until I can verify how they're wired. :)

schill
12-12-2011, 06:06 PM
Take a look at the red and black stripes that run along the contacts. All of the holes next to the black stripe are connected together (24 total). All of the holes next to red stripes are connected together (but not to the black holes) in two groups of 12. Note that there is a gap between the two red stripes. The two groups of red holes are not connected to each other. You can connect them by using a jumper wire between the closest holes.

softcon
12-12-2011, 07:52 PM
Since I can't see the stripes, and I didn't know they were there, I didn't think to ask someone else to check to see if such an indicator was present,

So, what you're saying is essentially, I was correct,in thinking that holding the piece vertically makes the holes on the left connected, and the ones on the right connected, but not to one another. This is what I thought. Basically, as long as I stay within the groups of six, I need not worry about jumpering the additional group of six holes.
In that case, I guess that means I had vdd/vss connected backwards. <sigh> I always double and tripple check those things before applying power, but guess I goofed on that one.
Thanks for the verification.

erco
12-12-2011, 09:43 PM
When in doubt, stick in a wire and bust out your multimeter for a continuity check. Better safe than smokey!

softcon
12-12-2011, 10:16 PM
Do you (or anyone for that matter) know where I can get an audible volt meter? A light is good, but it doesn't work for me most of the time, because I can't see the light unless it's really dark in the room. An audible meter would work wonders, so if anyone has any ideas, I sure could use one, to prevent furture mishaps. Thanks.

kwinn
12-12-2011, 11:19 PM
Do you (or anyone for that matter) know where I can get an audible volt meter? A light is good, but it doesn't work for me most of the time, because I can't see the light unless it's really dark in the room. An audible meter would work wonders, so if anyone has any ideas, I sure could use one, to prevent furture mishaps. Thanks.

I would suggest you make your own continuity tester using a PC speaker and a 555 timer chip. Very handy for the workbench.

softcon
12-13-2011, 01:39 AM
Are you referring to this: http://www.parallax.com/StoreSearchResults/tabid/768/List/0/SortField/4/ProductID/234/Default.aspx?txtSearch=555+timer from parallax? I looked at the data sheet, and must admit, I was completely lost. I'm sure the process is simple for someone who knows more than I do, but being new to the whole "build things myself" thing, I'm not sure what to do with this (yet). Any assistance would be appreciated.

ElectricAye
12-13-2011, 02:05 AM
... I'm sure the process is simple for someone who knows more than I do, but being new to the whole "build things myself" thing, I'm not sure what to do with this (yet). Any assistance would be appreciated.

I'm not sure what format would be best for you, but you might try googling "555 tone generator" and check out what comes up.

erco
12-13-2011, 02:12 AM
Here's a $5 continuity tester that lights up: http://www.ebay.com/itm/Leviton-Electrical-Continuity-Tester-49661-/230708409108?pt=LH_DefaultDomain_0&hash=item35b74af314

You see you could make one yourself, too, with an LED or a buzzer/beeper. Cheap multimeters also have a continuity test function, some with audio beepers.

erco
12-13-2011, 02:36 AM
Here's one cheap meter with an audio beeper: http://www.ebay.com/itm/UNI-T-UT33D-Digital-LCD-Palm-Size-UT-33D-Precision-Handheld-Digital-Multimeter-/150718836273?pt=LH_DefaultDomain_0&hash=item23178aee31&autorefresh=true

softcon
12-14-2011, 02:35 PM
Upon further reflection, I realize I thought the pins were connected opposite of the way they are.
I'd assumed, that since there were two rows of pins, each pair (what I now know to be red/black pairs) were connected. I'd plugged my 2x16 screen into the black side, then plugged jumper wires into the red side, wrongly assuming they were paired off. As a result, ground, power, and data were all together on one circuit on the display, as was vdd, vss, and p0 on the stamp once all was connected. It's no wonder the stamp no longer works. <sigh>. Well, now I know. :)
So, Parallax is in line to sell another basic stamp in January, along with a super carrier board so I can begin playing with the javelin stamp I got this month.
Next thing to try is to test the ds1620 chip that was also plugged into the stamp at the time of it's demise. I had resisters on the data pins, so they're probably safe, but I just had jumper wires on the vdd/vss pins, so hopefully they didn't get too large a dose of wrongness. :)
I'll plug it into the propeller board, and see if it still operates. I hope it does, though replacing the ds1620 is considerably cheaper than replacing the bs2.
Anyway, I still want to thank Parallax for making me aware of the fact that I *can* still do this stuff, even if there a few mishaps along the way. And the folks on the forums are great too. Keep up the good work guys. I'm sure I'll be here with more questions/escapades as time permits.