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1  Using Arduino / Microcontrollers / Re: existentialist question: why arduino leonardo Takes that name? on: August 19, 2014, 02:41:28 pm
@KeithRB +1
Too Funny.. ROFL

Doc
2  Using Arduino / Microcontrollers / Re: Arduino pro micro atmega32uf no aref pin? on: August 18, 2014, 11:16:43 pm
The LM7805 isn't a good choice for a voltage reference for two main reasons, One is that Accurate ones are scarce. Production starts IIRC @ +/- 5%.
The second is the quiescent current or no load current is about 10 mA.
Good accurate devices such as the Analog Devices part or an equivalentcan be found in several places with prices comparable to Fleabay and one to 3 day shipping.. Microchip sells several devices that should work well and at relatively low cost in 5 piece quantities, I think singles are available but I can't remember for sure and TI will sample as well as will National Semiconductor in 1 to 3 quantities for trivial parts.
As I remember I paid about $0.55 ea for 5 TO-89 MCP1702's and about the same for 5 TO-92 MCP 2703's in addition they are available in 50 mV output voltage increments from ~1V to 5V and at current levels to 250 mA (TO-89) and with voltage inputs from Vout + ~.3V to 16V max. Although this is not a reference device, Per Se, it is an example of what can be found easily and inexpensively including really accurate parts too, Should you require them.
Finally several of the companies offering liberal samples also offer free or relatively inexpensive shipping...

Doc
3  Using Arduino / Microcontrollers / Re: attiny 85, any pointers?/ on: August 17, 2014, 10:55:13 pm
In re-reading your last post I realized I'd overlooked one crucial point.. When Stanley forked the nRF lib he rewrote both the Mirf and SPI libs
to accommodate the USI port available from the  Tiny 84 & 85's.  Due to the flash restrictions imposed by the 'small' code space.
This might help you in your search.
An Arduino port of the tinkerer.eu library. It works with most nRF24L01+ modules.

http://www.arduino.cc/playground/InterfacingWithHardware/Nrf24L01


For this fork, I include :-
* SPI85 libs for attinyXX support
* attiny84 examples codes working with RF24


From xdarklight/arduino-nrf24l01 forks :-
This fork includes the following changes:
* Added support for the SPI85 library on ATtiny85 chips.
* Compatible with ATmega and ATtiny chips (tested with ATtiny85).
* Can connect to devices using the RF24 library by setting
  "Mirf.baseConfig = _BV(EN_CRC) | _BV(CRCO);" before calling
  "Mirf.config();".
* Reduced binary size.

Other information:
* This library supports changing less popular registers without
  having to "hack" the libraries code. An example for changing
  the RF_SETUP register:
  "Mirf.configRegister(RF_SETUP, _BV(RF_DR_LOW));"

Stanley
stanleyseow@gmail.com


There is code for both the tiny 84's and the 85's in the examples.

Doc
4  Using Arduino / Microcontrollers / Re: attiny 85, any pointers?/ on: August 17, 2014, 03:44:19 pm
From Stanley's advice I removed ALL of the nRF24lXX references from my IDE installation [ver 1.05] to avoid possible lib incompatibilities, at Stanley's advice) I then downloaded the nRF24l01 library for the Tiny84 and installed it under Users/../.My Documents/Arduino/libraries/... and was able to compile and program an '84 with the library.. although I never got around to testing it.
I had several issues, initially in comping his code and I PM'ed him about the issues.
His advice is what I mentioned above and it worked.
The '85 is a really nice little controller but there is one free pin... Two IF you disable the reset... I'd advise you to consider the 84... Most highly.
Stanley is approachable... PM him or extract his contact info from the Google search I mentioned and email him...

Doc
5  Using Arduino / Programming Questions / Re: calling pinMode in the constructor on: August 17, 2014, 03:08:36 pm
F Malpartida's Liquid Crystal library?.. It does handle several different serial implementations.. I use the one for the I2C implementation  using a PCF8574. It is more than fast enough for my purposes..

Doc
6  Using Arduino / Microcontrollers / Re: attiny 85, any pointers?/ on: August 17, 2014, 02:57:31 pm
Yes, A forum member .. Stanley Seow has done it for both the '84 and '85.. Among others, by fixing or rewriting the MIRF class..
My best advice would be to Always remember that "Mr. Google" is your best research friend..
Google sez.. "73400" replies to Stanley Seow.... And this is I think the most salient...
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CB8QFjAA&url=https%3A%2F%2Fgithub.com%2Fstanleyseow&ei=BQjxU4SLCoGEogSMx4D4BA&usg=AFQjCNGL1gTiuLRqLosVVvQLY2G92hvC5A&sig2=fR2U93rr9S6sK1shpp_dhw&bvm=bv.73231344,d.cGU
Also search the Forum for nRF24l00 + Stanley Seow, It returns 7 replies...

Doc
7  Using Arduino / Audio / Re: Difference between two circuits on: August 08, 2014, 02:20:34 am
Find a copy of Don Lancasters OP-AMP Cookbook and use it to  make a pre-amp using an LM358.  Set the gain of the LM358 to 100. Set the gain of the LM386 to 20 (No bootstrap capacitor) and use a simple pot to control the pre-amp output.
With the suggested gain(s) set in the dc feedback components of the Pre-Amp. For a millivolt input you should be capable of 20 mV to 2V output swing. If you use the inverting op-amp input as the audio input you can vary the DC output offset of the Pre-Amp from +1.25V to +3.75 V by connecting the stationary leads to Vcc and Gnd. The Wiper (center lead) goes to the non inverting op-amp input. With this method you can center the output @ 1/2 the power supply...
With any (almost) newer Cmos op-amp (I like and use LMC662's) both input and output can swing from rail to rail. The older devices... LM324, LM358, LM2904 the output cannot swing less than 2 BE (diode) drops from either supply rail...
You can also connect 2 or 3 sections of a CD4069UB in series and connect a 100k resistor from input to output and easily achieve 30 to 50 DB of gain (1000 to 100000). don't forget to use dc blocking caps on input And output of the 4069UB as well as a 220 uF bypass capacitor..Note: the CD4069UB is capable of linear operation and it will work from 3V to 15 Vcc.
Many if not all common Electret microphones have a j-fet buffer, internal to the microphone and  do require a volt or two as bias voltage for the J-fet in the microphone... a 1K resistor in  series with a 4K7 and a 10 uF cap from that junction is required as the mic bias Must be stable and clean. The open end of the 1K resistor goes to Vcc and the open  end of the 4K7 resistor goes to the mic output and to the audio amp input. The negative end of the 10uF filer cap goes to ground.

Doc
8  Using Arduino / Programming Questions / Re: Star Wars Imperial March With Piezo on: August 08, 2014, 12:30:16 am
Prove to yourself first that you're not a fool... The rest will follow... Once you learn to read first and talk second...
"Better to keep ones mouth shut and be thought a fool than to open it and remove all doubt..."

Doc
9  Using Arduino / Microcontrollers / Re: Security of Software on: August 07, 2014, 12:47:14 am
@ OP, you might read this too...
http://forum.arduino.cc/index.php?topic=259388.0

Doc
10  Using Arduino / Microcontrollers / Re: Please Help - Programming PIC18F2525 using Arduino on: August 05, 2014, 03:53:45 pm
Your English is quite good enough to be understood, Perhaps not idiomatic but certainly accurate enough.
Did you notice 2 common things about the three "References" you referred to?...
First they refer to a low end 14 bit core (Pic's use data and instructions in each line of code), equivalent (in code space) to a Tiny 4313...
Second that none seemed to work ... I didn't see anything similar to code and a wiring diagram.
I don't know about "Real Quality technical discussion, especially as one of the articles was 4 years old, another merely 2 years old, and for the last reference (the one only a year old doesn't have enough information to finish the project outlined in the thread.
While the device you wish in not only newer and has a slightly different programming method...

Doc
11  Using Arduino / Programming Questions / Re: Re-purposing the code for a digital potentiometer? on: August 04, 2014, 04:44:12 pm
try this...   http://forum.arduino.cc/index.php?topic=125908.0. Second entry on the Microcontrollers page...

Doc
12  Using Arduino / Microcontrollers / Re: AVR ATMEGA16A on: August 03, 2014, 01:43:45 pm
Since a great deal of the Arduino environment and sample code is devoted to the ATMega328P... Why the choice of the ATMega16?

Doc
13  Development / Other Hardware Development / Re: 16x2 LCD module 3 wire Interface using SHIFT register on: August 03, 2014, 12:35:20 pm
Try this first... It's already been done and rather well at that... 1602 and 2004 displays serial, OR parallel 74C165, CD4094 and 74HC595...
https://bitbucket.org/fmalpartida/new-liquidcrystal/wiki/Home

Doc
14  Using Arduino / Programming Questions / Re: Parsing GPS data on: August 03, 2014, 03:02:05 am
The answer is what makes programming fun and useful (Because it does cause one to think)... I don't have any suggestions... However you might go back to the TinyGPS++  page and leave a question... Mr Hart seems to be a very nice and helpful person in all I've read on his blog... were I to guess it might be a re-arrangement of the order of the called functions that is at the root of your problem... and although I've used many GPS devices (Still have 4 working devices) I've found that sometimes reordering one or more functions fixed several issues I've had in the past...
But, A coder,  I ain't...
I am an old hardware designer learning the language just to keep young and hopefully stave off the eventual fossilization of the mind...
Original high current rectifier http://commons.wikimedia.org/wiki/File:Tungar_bulbs.jpg#
They had a really pretty blue glow that could cause UV burns to the skin... when used @ high (10 - 20A) current, if the exposure was long enough

Doc
15  Using Arduino / Programming Questions / Re: Parsing GPS data on: August 02, 2014, 10:49:56 pm
Me Again... I do hope? that you understand that making GPS position measurements are ONLY valid outside where the GPS receiver has a good view of the whole sky and +/- 10 meters accuracy is considered fair to good... So, If your "Way-points" need to have better accuracy than 10 meters you might consider another means of using the GPS data...
I'd Highly recommend you reading this first...
https://www.google.com/search?q=Wiki+GPS+Accuracy&rlz=1C1CHFX_enUS594US594&oq=Wiki+GPS+Accuracy&aqs=chrome..69i57.18839j0j4&sourceid=chrome&es_sm=122&ie=UTF-8...  "Wiki GPS Accuracy" was my search phrase..
There were 8 responses, ALL have a bit or two that would be useful for your project.
Google First, Arduino Forum, Second.
Mr Google is your friend....

Doc
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