Specs for LED holes on A64-DB-2G-Rev B
#1
Question 
What can you tell us about the LED holes on the A64-DB-2G-Rev B board?

What are the power draw limits on the two pairs? Are they already set to indicate anything in particular (e.g. power, r/w)?
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regards,
J. Ouellette
    A64-DB-2G-RevB (2016-03-21)
    +WiFi/BT +IR
    Android Lollipop
    Ubuntu/Xenial 16.04LTS/3.10.102-2-pine64-longsleep (64GB)
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#2
(07-01-2016, 05:09 PM)jwouellette Wrote: What can you tell us about the LED holes on the A64-DB-2G-Rev B board?

What are the power draw limits on the two pairs? Are they already set to indicate anything in particular (e.g. power, r/w)?

Not sure on the power draw limits, but I think the resistors are configured for a 5ma draw so you can use any normal 5mm or 3mm led... although a 3mm led is a better fit as 5mm is a bit tight! Have a look at this thread for more info on controlling the system led as it is a user programmable one. The other led is a charge indicator, but the PMIC (power management IC) doesn't appear to be configured to use it (on linux images anyway?).
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#3
(07-01-2016, 05:09 PM)jwouellette Wrote: What can you tell us about the LED holes on the A64-DB-2G-Rev B board?

What are the power draw limits on the two pairs? Are they already set to indicate anything in particular (e.g. power, r/w)?

The IO pin maximum current is 40mA from A64 datasheet, and you can check more info from the A64 datasheet located at Pie64 wiki site. Just use the 3mm LED as pfeerick suggested.
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#4
Wink 
Thanks!
--
regards,
J. Ouellette
    A64-DB-2G-RevB (2016-03-21)
    +WiFi/BT +IR
    Android Lollipop
    Ubuntu/Xenial 16.04LTS/3.10.102-2-pine64-longsleep (64GB)
    Debian 8.5 (jessie)/MATE 1.8.1/3.10.102-2-pine64-longsleep (64GB)
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#5
I was thinking about hooking up one of these - https://www.adafruit.com/products/1621 - and attaching it to the back of the PINE A64 acrylic case, but these demand 20mA, not 5.
--
regards,
J. Ouellette
    A64-DB-2G-RevB (2016-03-21)
    +WiFi/BT +IR
    Android Lollipop
    Ubuntu/Xenial 16.04LTS/3.10.102-2-pine64-longsleep (64GB)
    Debian 8.5 (jessie)/MATE 1.8.1/3.10.102-2-pine64-longsleep (64GB)
  Reply
#6
hi, all you need to do is drive it with a transistor (2N2222) or a FET.

... very tiny current into the transistor results in large current flow (switch) through the LED and collector of the transistor.
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