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1  Using Arduino / Project Guidance / Re: Arduino fire alarm notification on: August 10, 2014, 02:29:54 pm
A fire Alarm uses device connected to a central control box, a domestic detector uses a chain of devices with 3 wires +,-, interconnect.
From what you describe, you have the domestic interconnected setup with 9v on the interconnect line.
Out of a pure safety aspect, use the interconnect to trigger a relay or similar device then use the outputs of the relay to trigger the pin on the arduino.

(IIRC) some makes and models may have an auxiliary interface module that you can connect to run and protect the arduino.
2  Using Arduino / General Electronics / Re: Adafruit neopixel ring and capacitors. on: August 09, 2014, 03:02:23 pm
Definitely not 1F, you'd have to wait rather a long time for the 5V rail to rise...
Also you need reasonable low ESR for decoupling and dual-layer caps may not
be good enough.

Thanks MarkT, that what I wanted to check, I'll go back and look for the recommended cap.
3  Using Arduino / General Electronics / SOLVED: Adafruit neopixel ring and capacitors. on: August 09, 2014, 01:36:13 pm
Sorry don't have an Adafruit forum account.

On the Adafruit web site the is a warning that there must be a big capacitor across the light rings + and - terminals. as this is powered by the same supply as an arduino (5V) would a 1F 5.5v electrolytic capacitor be ok? (yes thats 1 farad!)
4  Using Arduino / Microcontrollers / Re: Identifying boot loader on: August 02, 2014, 02:26:44 pm
I think you can not identify the boot loader ...  smiley-roll-blue
You can buy a programmer (or use an Arduino as ISP) and rewrite the bootloader with the Arduino IDE. That way you are sure you have latest boot loader.

Oh ok, thanks.

By the way, the version is "R3" : " Arduino Uno R3"

opps typo
5  Using Arduino / Microcontrollers / Identifying boot loader on: August 02, 2014, 07:46:00 am
I have a (G3) uno (extra pins) and its currently programmed with test code for a led project.

I have 3 more mega chips for this board that are lab led up as (UNO) but how do I tell what boot loader is actually installed if i just swap the chips around?


P.S. I hope that above makes sense.
6  Using Arduino / LEDs and Multiplexing / Re: TLC5974 outputs flickering on latch on: July 20, 2014, 09:45:57 am
No, only one about the TLC5940. Haven't read the datasheet in detail, but the block diagram looks very different. It looks like the TLC5940 contains an additional EEPROM, you can write to the shift register or the EEPROM and switch the outputs from one to the other. Also, I didn't see a note about the outputs being switched off on latch signal. It also features a grayscale clock output which could probably be used to sync the latch, as mentioned in the TI thread.

Opps sorry, my mistake, misread the number.
7  Using Arduino / LEDs and Multiplexing / Re: TLC5974 outputs flickering on latch on: July 19, 2014, 07:59:40 am
Have you discovered "Demystifying the TLC5974" its a free ebook and the author can be very helpful.
8  Using Arduino / Motors, Mechanics, and Power / Re: Stepper motor setup for Unimat Classic type tools. on: February 16, 2014, 03:02:09 am
Cnc routing of acrylic can be difficult to get acceptable results and tool coolant is essential.
Post routing the acrylic will also need annealing, especially if you want to glue it.

I tend to "Lap" the service to get a perfectly smooth finish before polishing and glueing. The device will be mostly for turning acrylic but semi accurate routing will be wonderful.
9  Using Arduino / Motors, Mechanics, and Power / Re: Stepper motor setup for Unimat Classic type tools. on: February 15, 2014, 10:08:39 am
A stepper is unlikely to be the correct choice for driving a tool bit. Among other things 300rpm is quite fast for a stepper motor. And they are likely to be too "jerky" to give a good finish.

A regular DC motor with reduction gearing would be much more suitable. Machine tools with speed control usually have a system to maintain a constant speed as the load on the tool changes. That probably requires some sort of feedback mechanism.

Can you provide a link to the Unimat tool you have?

Can you explain in more detail what you want to do. Your comment about the 12000 rpm motor probably has nothing to do with multiple axis control so the whole post is a bit confusing. This is essential before any guidance about types of motor etc can be given.
Thats wierd, I read that in the nema 17 specs on ebay but I havent seen it on any other post.
Also the power motor of the tool runs at 12,800 66w 12v.
I was hoping that a 300rpm stepper existed and was better the a geared motor running at 300rpm.


You will need stepper motors if you plan to control tool positions and you should use proper stepper motor drivers such as the Pololu A4988 (which may or may not suit your motors).

A Mega or Uno can easily control 3 axes but a lot may depend on how much computation is needed to interpret the movement instructions.

Are you aware of GRBL (use Google).

I looked at the ramps board should I decide to go cnc.
Nope, cnc is new stuff for me to explore. but just googled ans started reading.
The MKIII Uno is in the last place you left it (unless you employ a cleaner).
...R
Thanks, now I just wish I could remember where that was.
10  Using Arduino / Motors, Mechanics, and Power / Stepper motor setup for Unimat Classic type tools. on: February 15, 2014, 07:19:16 am
I suppose I could use a motor or double gear setup but ...

I have an arduino Mega 25** and the arduino motor shield. I have purchased one of these small multi-role tools for working on acrylic but they don't seam to be able to go below 12000 rpms the idea of adding a stepper motor to the setup makes me think that it could be a worth while upgrade but I have a few questions.

1, What sort of stepper would I need to run down to 300 rpm's and what kind of force can I expect from a stepper at this speed.
2, will the motor shield be able to handle the job I intend it to do?
3, where on earth did I put my MKIII uno?
4, would the mega be able to drive 3 axis?
5, should I dump the shield and use the Poulolo drivers and if so.
6 what combination should I get?
11  Using Arduino / Microcontrollers / Re: Using arduino's atmega328 standalone on: February 01, 2014, 02:04:15 am
Yes and it's normally known as a "Bare Bones" system.

Basically just the chip, required support components and components that make up the circuitry.
12  Using Arduino / Microcontrollers / Re: Standalone 3.3v Atmega 328p - Do I need a Crystal or Resonator? on: January 21, 2014, 04:11:49 pm

A risk with LiPo batteries is draining them too death.  You will need a cutoff.  Depending on what else is in the circuit you may be able to put the processor into Power Down sleep mode (after turning everything off) when the battery voltage reaches the floor.

This article has details about draining (and charging)...
http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries

The problem is not with draining them to death, it causing voltage to drop so low that a chemical trip cuts in. There are ways to revive them and restore them but it can be risky if done wrong! (I have revived 3 lipo's so far but they were all only a year old when they tripped!)
13  Using Arduino / LEDs and Multiplexing / Re: TLC5940, problems with leds staying on after they are faded on: December 14, 2013, 03:22:12 pm
Not necessaries connected to your problem but your missing the bypass capacitors across the TLS's + and - line. (VSS & VDD)
14  Using Arduino / General Electronics / Re: m2 memory card instead SD card on: October 16, 2013, 02:40:16 pm
What is a "m2 memory card" ?

Memory Stick Micro!

Miniature version of the sony memory stick and memory stick pro duo!

I doubt it as there different formats and shapes!
15  Using Arduino / Audio / Re: fully assmbled wave shield on: September 08, 2013, 04:11:37 am
Honestly, if you follow the instructions, the Adafruit wave shield is very easy to assemble.
One could even go so far as to say that its an ideal beginners project!
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