Attached are two photos, one taken in the water (note the depth) by MBARI’s remotely operated vehicle (ROV). The large back tubes contain a large number of alkaline batteries plus the Beagle board as well as some power and analog electronics. The other photo reveals the Beagle, hard drive, etc.
The small cylinder marked “79” is an acoustic transponder that pings back in response to a chirp from a ship. The response from the pinger allows the determination of the range and bearing to the submerged equipment. It’s very useful to know where you left something, when it comes time to retrieve it from Davy Jone’s locker.
The other protuberance at right angles to the large black tubes is the hydrophone that captures sound in the water.
Our app requires about 1.5 watts when collecting audio and roughly, 3 watts when writing to the hard drive which only occurs about every ten to twenty minutes. A large buffer in DRAM allows a 1% duty cycle for hard drive power but I don’t know how to turn the EHCI power switch off or on.
Any ideas on how to control the EHCI power switch from a user application?
A free “shrunken head” will be given to the first correct suggestion. We put Styrofoam wig heads on the ROV; the pressure shrinks them and makes interesting, if useless trinkets.
Run, Beagle, run…
Wayne
Happiness does not come from having much, but from being attached to little. |
This is really great!!! I guess we need to add to our Beagle training teaching it how to swim, just in case.
As to you power off question, I know how to do it, just write to the LEDA bit of the TPS65950. Now, from user space, that is another issue. Let me talk with one of the SW guys and see what I can come up with.
Gerald
Wayne Radochonski wrote:
Any ideas on how to control the EHCI power switch from a user application?
A free "shrunken head" will be given to the first correct suggestion. We
put Styrofoam wig heads on the ROV; the pressure shrinks them and makes
interesting, if useless trinkets.
can I supply some real heads to be treated that way?