Search found 839 matches

by esklar81
Mon Dec 12, 2011 8:56 pm
Forum: SparkFun Product Questions
Topic: Remedial embedded system design and manufacturing books?
Replies: 1
Views: 308

Re: Remedial embedded system design and manufacturing books?

tlr, It's not obvious to me that books are the best approach. I suggest you invest in a SparkFun Inventor's Kit , work through the exercises in it, then get creative. There's lots of documentation (including tutorials) available through SparkFun and elsewhere on the web. If/when you get stuck, just...
by esklar81
Thu Dec 08, 2011 9:44 pm
Forum: SparkFun Product Questions
Topic: Conductive Thread Question
Replies: 4
Views: 1411

Re: Conductive Thread Question

Daisy, First, welcome to SparkFun fora! I'll start off by stating that I have no experience with SparkFun's e-textile offerings. That said, let me see if I can be of some help. 1) The ohm, for which the symbol is Ω, is the unit of resistance. So, the lower the number of ohms/unit length, the more e...
by esklar81
Tue Dec 06, 2011 9:28 pm
Forum: SparkFun Product Questions
Topic: Newb Question - Dual Voltage Circuit Interactions
Replies: 2
Views: 303

Re: Newb Question - Dual Voltage Circuit Interactions

grantkaye, How are you turning the 12V motor on and off? How much current does it draw? You are on the right track about using the 3.3V signal to open a relay that feeds the motor. The details, such as what components you'll need, depend on what you already have and how much current the motor draws...
by esklar81
Mon Dec 05, 2011 8:26 pm
Forum: SparkFun Product Questions
Topic: Arduino Pro 328 - 5V/16MHz
Replies: 2
Views: 323

Re: Arduino Pro 328 - 5V/16MHz

rrc1962, Without looking at the datasheet (If you had provided a link, I might have looked. :wink: ), it may be that the 40 mA is per terminal and the 150 mA is maximum total of all active pins. As a general rule, though, one should not drive an inductive load (such as a relay) directly with the ou...
by esklar81
Sat Dec 03, 2011 6:37 pm
Forum: SparkFun Product Questions
Topic: 30 potentiometers & arduino [HELP]
Replies: 6
Views: 715

Re: 30 potentiometers & arduino [HELP]

EvilWizard, I second Mee_n_Mac's suggestion that you investigate analog multiplexers (MUXs). I don't think "daisy-chaining" (connecting the output of one device to the input of the next) will serve you at all well, but you can connect large numbers of potentiometer high ends to one voltage supply a...
by esklar81
Fri Dec 02, 2011 10:07 pm
Forum: SparkFun Product Questions
Topic: Breadboard ?
Replies: 4
Views: 486

Re: Breadboard ?

Z.K., Why not just "widen" the center channel so that the pins of your device fall in the holes closes to center? It appears to me you could do this by cutting the board along the channel, then spacing the segments as needed. Alternatively, if you placed two segments such as these next to each othe...
by esklar81
Fri Dec 02, 2011 1:06 pm
Forum: Arduino
Topic: pls: GSM module for making phone calls
Replies: 2
Views: 452

Re: pls: GSM module for making phone calls

mw78, It is said that gods help those who help themselves. In (at least) that way, forum participants are god-like. Here's a four-step plan for you: Go read this. Search the SparkFun fora for relevant threads. If you don't find there what you need to get yourself started, search the rest of the hum...
by esklar81
Fri Dec 02, 2011 12:16 pm
Forum: SparkFun Product Questions
Topic: Schematic/wiring question
Replies: 2
Views: 383

Re: Schematic/wiring question

scampa, It looks to me that: a) when nothing is plugged in, pins 1 and 2 are not connected and pins 3 and 4 are connected to each other and b) when the correct plug is inserted, pin 1 is connected to the center of the plug, pins 2 and 4 are connected to the outside of the plug, and pin 3 is not con...
by esklar81
Thu Dec 01, 2011 9:41 pm
Forum: Arduino
Topic: Ardubot with wireless Bluetooth
Replies: 2
Views: 505

Re: Ardubot with wireless Bluetooth

samman946, It does not look to me like an issue with a buffer. Each of your subroutines turns on the H-bridge for its intended configuration, but nothing but the "stopmotor" subroutine turns the H-bridge off. Therefore, unless you send a subsequent command, the H-bridge stays where you put it and t...
by esklar81
Tue Nov 29, 2011 9:08 pm
Forum: SparkFun Product Questions
Topic: Serial motor driver compatible with dual motor gearbox?
Replies: 1
Views: 261

Re: Serial motor driver compatible with dual motor gearbox?

James, That sounds like a power supply problem to me. Your comment "the motors aren't getting enough torque" may well be a step in the right direction. To oversimplify vastly: for a brushed DC motor, voltage is speed and current is torque. Here're a few things to get you started: What are you using...
by esklar81
Tue Nov 29, 2011 8:28 pm
Forum: Arduino
Topic: Breadboards....I don't understand.
Replies: 1
Views: 530

Re: Breadboards....I don't understand.

Jeremy, Let's start with a basic question: By "Arduino chip", do you mean one of these: http://www.sparkfun.com/products/11021 or one of these: http://www.sparkfun.com/products/9061 or something else? More generally, if you include links to the product pages in your posts, you'll get much better an...
by esklar81
Wed Nov 16, 2011 10:05 pm
Forum: SparkFun Product Questions
Topic: How to use the stem of a small DC motor?
Replies: 6
Views: 613

Re: How to use the stem of a small DC motor?

Other thoughts: If you do find a gear, pulley, or coupling with a set screw, you may want to file a small flat onto the shaft against which to tighten the set screw. Otherwise, if you ask for much torque, the shaft is likely to spin inside the power transfer device you connected to it. I've had mod...
by esklar81
Wed Nov 16, 2011 9:48 pm
Forum: SparkFun Product Questions
Topic: assembly program for serial lcd
Replies: 1
Views: 331

Re: assembly program for serial lcd

phijoh, May one ask "Why?"? Unless you need to shave milliseconds, why not write in a higher level language? Also, if you don't tell us on what you're looking to run the assembly code, how is one to know where to start of if what one has in hand is useful? (In the interest of full disclosure: I'm n...
by esklar81
Wed Nov 16, 2011 9:39 pm
Forum: SparkFun Product Questions
Topic: SF spectrum analyzer connected to relays.
Replies: 4
Views: 583

Re: SF spectrum analyzer connected to relays.

Roms, Here are some suggestions: Go to the product page for the spectrum analyzer and read the comments. Try the code reported (in them) to work. Check to make sure you are using the correct pins. The analog and digital pins are different, and your use of a digital function (pinmode) on what you ap...
by esklar81
Wed Nov 02, 2011 7:57 pm
Forum: SparkFun Product Questions
Topic: Moisture sensor source, or idea?
Replies: 6
Views: 714

Re: Moisture sensor source, or idea?

It seems to me that what you need to change is flow rate, not timing. How about restricting water flow. If you were to do that by putting a misting nozzle at the current water discharge point, you could probably improve your humidification speed and drive your water waste to nearly zero.

Eric