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Comment: Re:rpi comparison (Score 3, Interesting) 41

by Change (#49425101) Attached to: Armstrap Claims to Make ARM Prototyping Easier (Video)

ARM has two general series of processors, the A series, or application processors, and the M series, or microcontrollers. Microcontrollers (such as the STM32F4 in the Armstrap boards) are designed for low-power embedded device use, you *might* run a specialized RTOS on one, but usually it's just your code, running bare-metal. An application processor, such as what you have in your smartphone or in the Pi, is a more general purpose computing core, running faster, taking more power, and using a full OS for resource management and process scheduling. Also, generally, microcontrollers have their own built-in RAM and Flash, while application processors use external RAM and storage (the Pi looks like the RAM and CPU are one, but in reality they're two separate dies, stacked up within the same package, while micros have everything on the same die).

Comment: Comparison to STM32F4 Discovery boards? (Score 2) 41

by Change (#49425059) Attached to: Armstrap Claims to Make ARM Prototyping Easier (Video)

ST makes several ARM M4F based dev/eval boards with built-in JTAG and a few additional chips thrown in to play with (I think accelerometers and MEMS microphones are common). They cost around $15-$20... go to http://www.st.com/web/catalog/... and check the box for STM32F4 under Supported Devices.
So, with what I suspect is the benefit of manufacturer loss-leader subsidies on the Discovery boards, why would I spend $40-$60 more on a dev board?

Comment: Tools for modifying open hardware designs (Score 3, Interesting) 78

by Change (#49235615) Attached to: Why We Need Free Digital Hardware Designs

OSHW has a bit of a difficulty associated with it, and that's the tools used to view/edit the designs. Many proprietary PCB CAD packages are offered in free-as-in-beer versions for boards up to a certain size or pin count, but then you're locked into that package. If you want to take that design and expand it beyond those constraints then you're stuck buying into the next step up of the software, or you have to fully re-design (schematic capture and layout) in another tool. Fortunately KiCAD (http://www.kicad-pcb.org/) seems to be picking up a bit of steam, but for those already using other tools, unless they're deep believers in the full open toolchain philosophy, what incentive do they have to switch packages (and re-implement their existing designs in that new package)?

Comment: Comparison chart (Score 4, Informative) 81

by Change (#48711865) Attached to: Ringing In 2015 With 40 Linux-Friendly Hacker SBCs

I was actually looking at several of these boards recently, trying to find all the multi-core options at/below about $100. I put together a Google Docs spreadsheet comparing various specs (#/type/speed of cores, RAM, Flash, network, SATA, USB, RTC), I've got 18 on the list so far. Looks like I have a few more to add...

Comment: It has vision! (Score 2) 43

by Change (#47561827) Attached to: A Look At the Firepick Delta Circuit Board Assembler (Video)

This project appears to have computer vision for parts alignment, which is a HUGE deal for a pick-and-place. You need your machine to know if a component is oriented improperly in the reel, and to provide positive feedback on board position by referencing fiducials for accurate placement of fine-pitch components. Other pick-and-place projects I've seen in the past have been just standard 3-axis CNC gantries with a vacuum pickup, the addition of CV means it potentially can truly compete with the high-cost units.

Comment: My CFL lifetime depends on where they were bought (Score 1) 278

by Change (#47432777) Attached to: My most recent energy-saving bulbs last ...

I've bought a number of Feit Electric CFLs from Costco, and get at least a few years of regular use out of them. However, whenever I've bought the same brand from various local hardware stores (both mom-n-pop and big brand stores) I've had them fail within a few months. I'm not sure what's up with that, but that's my experience. I have yet to try any LED bulbs due to the up-front cost and the long life I'm getting out of my CFLs, and I have no use cases where dimming is necessary.

Comment: External yes, cards no (Score 1) 502

At work I have a HiFiMeDIY Sabre Tiny USB DAC ($30) as my work laptop's internal audio is full of noise (hissing that changes with system activity).
At home, my gaming machine uses its onboard audio interface, but sends digital audio out via SP/DIF to my home theater receiver for its DAC and amplifier.
I even have an external sound interface for ham radio use, a Tigertronics SignaLink USB that's just an external ADC/DAC with some filtering and isolation which interfaces with my radio for digital modes (such as PSK31 or RTTY).

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