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1  Products / Arduino Due / Re: Due pinout diagram on: April 03, 2014, 10:49:16 am
Thank you very much, this should help tremendously.
And I'm sure others will appreciate it just as much as I do.

Sam.
2  Products / Arduino Due / Re: How to generate SINE PWM on: March 20, 2014, 12:33:54 am
I understand the fun of hacking something to do something else. Your mention of the Holley carburetor is not really applicable, since the Holley carburetor was designed to do one thing, deliver the proper amount of fuel versus air mixture.. No matter how much you tweak it, it does the exact same thing as it was designed to do. Nothing more.
No microcontroller can be all things to all needs. There's always going to be something that it needs help with. And that's all I'm suggesting.

Even if he does not use a chip of this type, if this type of control is what he needs, At least we will better understand what his needs are.

Joe.
3  Products / Arduino Due / Re: How to generate SINE PWM on: March 19, 2014, 11:20:58 pm
Not sure exactly what you're trying to do, and from what I have read not many that has responded understand it either.
I do know that PWM Voltage control is directly related to the current draw Versus the current input in the circuit. The voltage is maintained by maintaining the current input.
Not directly regulating the voltage.

There are ICs out there that I believe will do what you need. This one might work for you.
http://www.ebay.com/itm/FCM8282-x2-3-Phase-Sinusoidal-Brushless-DC-motor-controller-FCM8282QY-/181228852417?pt=LH_DefaultDomain_0&hash=item2a3214d4c1.

Note: I have no information on this chip other than what the website gives me. This is just an example of what is out there. And at that price it should be cheap enough to experiment with.

Hope this helps.

Joe.

4  Products / Arduino Due / Re: How to generate SINE PWM on: March 19, 2014, 01:46:21 pm
I haven't been following this thread much, but if you're trying to drive a three phase motor, you need three equally spaced phases to do it. The Arduino due will only give you two.

Variable frequency drives very the frequency Of three sine wave generators. They do not actually use PWM. 

My advice is to change the motor to a single phase or DC motor. Or get a external Sine wave generator that will produce three Phase.
Joe.
5  Products / Arduino Due / Re: Due pinout diagram on: March 09, 2014, 07:51:25 pm
The spreadsheet is nice, But if the spreadsheet was all that was needed, this thread would never have been started.
the graphical representation of the board that is presented here is much easier to read and understand.
Being able to see and to locate each pen and its corresponding use is much better than a spreadsheet.
Although a spreadsheet can display more data, is just not the same.

Thank you for your reply and I will look over the spreadsheet.

Joe.
6  Products / Arduino Due / Re: Due pinout diagram on: March 09, 2014, 01:55:55 pm
Just wanted to thank you for putting out this diagram. It has helped a lot.

But I would like to have one addition to this diagram. The addition of quadrature inputs would be a great help.

Also, if you can make a second diagram that listed the primary pin designations and has a empty box so that the user can designate what pens are used for what purpose in their project, it would be very helpful.


Again, thank you, it has been a great help.

Joe.
7  Products / Arduino Due / Re: Frequency detection works with Uno, not with Due on: March 08, 2014, 01:27:43 pm

First of all, like you I am just beginning to work with the DUE. I'm not a programmer, just a hobbyist. So take everything I say with a grain of salt and investigate for yourself.

First let's talk about the differences between the standard Arduino platform and the DUE.

Port mode: although you can use port modes, they are intended for byte transfer of data. In my opinion Port mode should not be used for setting or resetting a individual pens. If anything else is hooked up to that port, it could have devastating effect on the accuracy of your data. When you declare that you're going to use pen mode, you should not use port mode. Always use the mode that you declare, and in the same context.

Timers: most Arduino's only have 1 timer. The DUE has several. You need to select which Timer you need to use.
The dude is not assume that you want to use any particular timer.

ADC: instructions used for the standard Arduino's is not the same as the DUE. For that reason all of your ADC errors are being seen as variables not instructions.

Interrupts: for most Arduino's, There are only a few interrupt Capable pens. Globally setting these interrupts and clearing them is not a problem. However on the DUE, every pen is interrupt ready. Globally setting these pens could have A devastating effect on any input. So global functions do not work on the DUE. Each needs to be set and reset individually.

You need to go through the tutorial for the Arduino due. Read it carefully and practice the examples until you understand how it works.

Hope this helps.

Joe


8  Products / Arduino Due / Re: Arduino Due - Compatibility with HDMI? on: February 28, 2014, 12:38:28 pm
If you need an HDMI output, And Arduino Compatibility, Try the pcDuino2.
https://www.sparkfun.com/products/12749.

 Features:

    1GHz ARM Cortex A8 CPU
    GPU: OpenGL ES2.0, OpenVG 1.1 Mali 400 core
    1GB DRAM
    Onboard Storage: 4GB Flash, microSD card (TF) slot for up to 32GB
    Arduino-Style Peripheral Headers
    HDMI Video Output
    Linux3.0 + Ubuntu12.04 and Android ICS 4.0 Supported
    0.1" Spaced GPIO Headers
    RJ45 Ethernet Connection and On-Board Wi-Fi Module
    Power Requirements: 2A @ 5VDC
    API to access the following interfaces:
        UART,  ADC, PWM, GPIO, I2C, SPI.
    Program in C, C++ with GNU tool chain
    Java with Android SDK
    Python

Joe.
9  Products / Arduino Due / Re: Arduino Due 2.8" TFT touch shield v1.0 from seed studio on: February 23, 2014, 12:42:36 am
I will give you the same advice I gave In another post Today.

First of all, I recommend using this shield that is compatible with the DUE.
"http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=121057447668".
It is compatible with both Standard 40 pin And 32 pin Displays. Make sure you check the pin out before you purchase.
It eliminates most of the compatibility problems that arise along with all the jumper wires that would be needed.

There is also a list of compatible boards that is in that Size and price range In the listing. Most of these boards are UTFT Library compatible.
Check with  "http://henningkarlsen.com/electronics/library.php?id=66" For compatibility list.

The link listed above has a touchscreen Library that may work with your display. Check the compatibility page.

Hope this helps.

Joe.
10  Products / Arduino Due / Re: Arduino DUE TFT screen compatibility on: February 23, 2014, 12:36:35 am
First of all, I recommend using this shield that is compatible with the DUE.
"http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=121057447668".
It is compatible with both Standard 40 pin And 32 pin Displays. Make sure you check the pin out before you purchase.
It eliminates most of the compatibility problems that arise along with all the jumper wires that would be needed.

There is also a list of compatible boards that is in that Size and price range In the listing. Most of these boards are UTFT Library compatible.
Check with  "http://henningkarlsen.com/electronics/library.php?id=66" For compatibility list.

Hope this helps.

Joe.
11  Products / Arduino Due / Re: 3.3v logic levels interface with standard TTL/CMOS logic - How to do it... on: February 07, 2014, 01:52:28 am
Follow-up to previous post: although I have been dealing with logic circuits since the mid-70s, I admit I am not up on the most current logic circuit family. So I decided to do some research and I came up with this:

http://en.wikipedia.org/wiki/7400_series

Scroll down to the lower two thirds of the page and you will find a chart giving various parameters of each logic circuit family up to about 2004. These parameters include logic family, circuit speed, voltage requirements and current draw. Interesting enough that the fastest chip that was listed here was the 74 "G" series which is a TTL circuit running at 1.125 GHz.

I just thought this might help someone when choosing logic circuits for their Arduino project.

Joe.



12  Products / Arduino Due / Re: 3.3v logic levels interface with standard TTL/CMOS logic - How to do it... on: January 31, 2014, 10:35:32 pm
" Please do not confuse TTL with 7400 series, TTL is transistor-transistor logic,
period.  These days noone uses TTL chips at all. "

I don't know where you get your information, but it is wrong. 4000 series is CMOS Which predates the 7400 series and is very rarely used today. Although many 74 series chips do use you CMOS logic, For instance the 54C and 74C series was CMOS.  7400 series was primarily TTL.  And if you look at the 74H series You'll find that the Numbers after the letters changed to 4xxx. The function of these numbers correspond to the 4000 series chip numbers, With very little variance.  That is a 74HC4060 will have the same function as a 4060 Chip, aThe "14 stage binary counter" . But using TTL voltage specifications.
If you want I can send you a copy of a page or two from the National Semiconductor data book from 1984 to prove it. Yes I have been dealing with them that long.

The 7400 series includes but is not limited to:

74 TTL.,
74ALS advanced low-power schottky.
74AS Advanced schottky.
74S schottky.
74L Low-power TTL.
54HC/74HC/54HCT/74HCT High-speed micro CMOS,
74 LS I in VLSI CMOS,

Joe.






13  Products / Arduino Due / Re: 3.3v logic levels interface with standard TTL/CMOS logic - How to do it... on: January 31, 2014, 05:19:29 pm
Note: the 74LVC245 Is a "Octal bus transceiver with direction pin with 5-volt tolerant inputs/outputs 3-State".
It is not specifically a logic shifter for individual bits. It will Shift the logic for a entire bite. Which is not recommended For a microcontroller, because any bit maybe set for output or input. If any two outputs are connected together it could cause problems or damage the microcontroller..Unless you are intending to shift one entire bite at a time, and all Bits are known to be either input or output, Do not use it.
Also note: This chip needs to be powered by 3.3 votes only.

Hope this helps.
Joe.
14  Products / Arduino Due / Re: 3.3v logic levels interface with standard TTL/CMOS logic - How to do it... on: January 31, 2014, 04:14:38 pm
This problem has been around since the early days of logic circuits.
When it comes to CMOS chips, There is no easy answer.
The original CMOS chips Ranged in voltage from 15V  and in some cases up to 30V.
I do not recommend using the older chips. However, current CMOS chips will run at 15V or 5V.
I have never tried to run true CMOS at 3.3V. If you're referring to the 74H series which is a CMOS -based " TTL " series, They normally run at 5V, check your data sheet. Some of these chips will run fine at 3.3 V.  Even if you run them at 5V, Going from 3.3 V to 5 V should not give you a problem. However, you will need a voltage divider when going in the opposite direction. A level shifter is always recommended.

All 7400 series TTL logic runs at 5V and maybe less, depending on the series. It used to be pretty easy to keep up with the 74xx series and the voltage that they would run at.  Now there are two many 74xx series to keep up with. Check the data sheet for specific specifications.

Note: some TTL chips put out a small current from the input side. The output of the preceding chip either pulls it low or forces it to go high. This voltage can cause erratic output if the input is not tied to either a positive or negative voltage. If the gate is not in use, always tie the input so it produces a LOW output. For this reason a logic shifter is always recommended when going from one voltage to another.

Hope this helps.
Joe.



15  Products / Arduino Due / Re: Can Arduino Due libraries be used on Atmel Studio? on: January 30, 2014, 05:02:47 pm
Note: an apparent bug has been found in the current version of Visual micro.
The bug was identified by someone in the visual micro group.
Apparently visual micro has problems when reading libraries using all  capital letters.
I have confirmed the problem When trying to compile the " UTFT.h " library.
Changing the library name to lowercase letters fixed the problem.

Hope this helps someone.

Joe
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