Search found 7 matches

by fmr300
Sat Jan 26, 2019 4:28 pm
Forum: SparkFun Product Questions
Topic: OpenScale question
Replies: 1
Views: 97

Re: OpenScale question

Since I (somewhat) slandered OpenScale's firmware, I thought I'd repost a retraction. I mostly figured out my problems and now have it working quite well. Initially when I put the same voltage in both S+/S-, I expected a near-zero raw value, so was surprised at the large raw number. Turns out it was...
by fmr300
Sun Jan 13, 2019 5:26 pm
Forum: SparkFun Product Questions
Topic: OpenScale question
Replies: 1
Views: 97

OpenScale question

I'm waiting on the load cells to arrive, so just did a simple experiment on the OpenScale, and it has me perplexed. Thought one of you may be able to help: I put two series 1K resistors between E+ / E- , then tied their midpoint to A+ / A- . This sims the loadcell's outputs being perfectly balanced ...
by fmr300
Sat Dec 29, 2018 11:18 am
Forum: SparkFun Product Questions
Topic: OpenScale - Load-cell vs strain-gauge
Replies: 2
Views: 58

Re: OpenScale - Load-cell vs strain-gauge

Thanks DanV - that's a far better article than what I had found so far, and does a GREAT job in explaining.... appreciated !
by fmr300
Fri Dec 28, 2018 2:17 pm
Forum: SparkFun Product Questions
Topic: OpenScale - Load-cell vs strain-gauge
Replies: 2
Views: 58

OpenScale - Load-cell vs strain-gauge

I'm confused on how a 4-wire load-cell, having 4 strain-gauges (like a bathroom scale) works, and am hoping someone can help me. Just for reference, I'm an EE so you shouldn't have to start with Adam&Eve. When the Combinator 'combines' 4 strain-gauges, it appears to put the 4 resistances into a Whea...
by fmr300
Sat Dec 22, 2018 2:12 pm
Forum: SparkFun Product Questions
Topic: How does Combinator work?
Replies: 0
Views: 63

How does Combinator work?

The combinator allows 4 load-cells to be combined (in a Wheatstone bridge config) and then connected to the amplifier board (HX711). But how does this work? Let's say the load-cells all start at the same resistnace, and there's one in each corner of a scale platform. If the weight is then applied to...
by fmr300
Fri Feb 20, 2015 11:36 am
Forum: SparkFun Product Questions
Topic: Use 'Pocket AVR Programmer' in AVR
Replies: 2
Views: 463

Use 'Pocket AVR Programmer' in AVR

Does anybody know if this programmer can be used directly with AVR Studio ?

I currently use an "AVRISP mkII" for programming AVR's, and that is directly selectable from AVR Studio.... ie, does the pocket programmer act like one of the selectable programmers in AVR studio?

tnx,

-mark
by fmr300
Sun Dec 20, 2009 9:04 am
Forum: SparkFun Site Questions/Comments
Topic: Peter Stonard's Holiday Lights PCB's
Replies: 1
Views: 640

Peter Stonard's Holiday Lights PCB's

New member - not sure if this is a reasonable place to post this question so will pre-apologize if not. Can any forum members help me determine how to find info on ordering PCB's for Peter Stonard's "Holiday Lights" project posted in NutsAndVolts in Nov2008 ? I believe he made the PCB's available, b...