Powering a QS board
Buck Rogers
Posts: 2,161
Hello!
I believe we addressed this one before, that of powering a QS board, in this case a REV. A one, via the VDD and VSS lands on the board itself. Instead of via the USB port. But I cannot seem to be able to properly find it.
So is it definitely possible to power one via those holes, from a 3V supply using, a pair of either AA cells in series, or a AAA cells also in series? Now I tried one of those using a switched battery holder and connected the leads to appropriate holes, and found the power light, ah, light up. And the currently resident program, the demo one worked.
This is in connection to "Translating the Arduino Sketches into a SPIN function"
Now in one called, "Still thinking about the one labeled "Translating the Arduino Sketches into a SPIN function" ", and then in that one I'd gotten reminded of this one,
"P8X32A Quickstart board power supply without USB?"
I just looked over that one. The included photos in one of the messages did not of course properly translate to the newer Forum, which I wasn't surprised over, but in using those two connection points for powering the thing, versus points labeled 39 and 40, but there's still a discussion waiting to be held here. I know @"Duane Degn" this is an interesting issue again. But given the circumstances, it's still an needed thing.
All of that is certainly valid, but I am simply wondering if nothing else has changed.
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Mascot away.
I believe we addressed this one before, that of powering a QS board, in this case a REV. A one, via the VDD and VSS lands on the board itself. Instead of via the USB port. But I cannot seem to be able to properly find it.
So is it definitely possible to power one via those holes, from a 3V supply using, a pair of either AA cells in series, or a AAA cells also in series? Now I tried one of those using a switched battery holder and connected the leads to appropriate holes, and found the power light, ah, light up. And the currently resident program, the demo one worked.
This is in connection to "Translating the Arduino Sketches into a SPIN function"
Now in one called, "Still thinking about the one labeled "Translating the Arduino Sketches into a SPIN function" ", and then in that one I'd gotten reminded of this one,
"P8X32A Quickstart board power supply without USB?"
I just looked over that one. The included photos in one of the messages did not of course properly translate to the newer Forum, which I wasn't surprised over, but in using those two connection points for powering the thing, versus points labeled 39 and 40, but there's still a discussion waiting to be held here. I know @"Duane Degn" this is an interesting issue again. But given the circumstances, it's still an needed thing.
All of that is certainly valid, but I am simply wondering if nothing else has changed.
---
Mascot away.
Comments
38 - 3.3V
39 - Ground
40 - 5.0V
If you want to power your quickstart through the USB port without a computer, connect a 1K resister from pin 38(USB_Power_EN) to ground. That will allow you to power from a USB wall wart.
Jim
Jim, these are all Rev, A boards. The site says that Rev. B can be powered via the USB port. Was that feature* fixed in the revision? That function I do understand from previous discussions.
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*Added by mascot.
Mascot not accepting donations or food this week.
I believe Rev B boards made it easier to accept 5V over the USB connection without having a USB signal. Rev A required the extra step described by Jim.
The last two pins on the QuickStart header are Vin and Vss (aka GND). You can apply ~5V here to power the board. Four NiMH cells is just right for powering the QuickStart. Some connection options are discussed in this thread.
I add female headers to the "Vdd/Vss" holes on the QuickStart and a pair of male headers to the Vin and Vss pins.
Here's a photo showing a battery pack connected to the male headers.
Here's another photo showing the male headers directly above the "u" in the silkscreened "Quickstart."
The male pin directly above the silkscreened "u" is ground (Vss). The male pin behind this ground pin is Vin. Vin may be used as a (low current) 5V source when the board is powered from USB.
The silkscreened text "VDD" and "VSS" are used to label the holes to the right of the text. In the above photos, these holes are populated with a female header. "VDD" is 3.3V. This 3.3V is produced from the regulator on the QuickStart board. These VDD/VSS pins may be used to power 3.3V devices. The above photos show a small Nordic nRF24L01+ module being powered from the QuickStart's onboard 3.3V regulator.
The pin to the left of the silkscreened "VDD" is Vin. The pins to the right of the silkscreened "VDD" are connected to the 3.3V power rail.
It case anyone reading isn't already aware, the holes in front of the 40-pin female header, have some electrical connections as the 40-pin female header.
If anyone has a Brother label maker they can print out labels similar to the ones shown in the photos. I believe the label file is attached to one of the posting the above linked thread.