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[on:]

Hi,

would someone be so nice and tell me whats the difference between this Tosduino Mega2560:
http://www.tinyosshop.com/index.php?route=product/product&product_id=175

and mega 2560?

The Tosduino Mega2560 costs 25€ and the mega2560 costs 50€ which is double the price.
And on ebay i see mega2560 boards for like as cheap as 18€, mostly from hongkong.

Except from the colour red i dont see any differences, what are they?

[Reply #1 on:]

Except from the colour red i dont see any differences, what are they?

One supports the Arduino team, including covering the cost of maintaining this forum. One does not.

One is fully supported by quite knowledgeable people. The other may not.

One is subjected to rigorous quality control. The other may not.

One uses quality parts, properly assembled. The other may not.

[Reply #2 on:]

thx for the answer.

is there something like inbetween that is supportive but not as harsh double the price aka 50€, like uno but with those 16 analog?

[Reply #3 on:]

More analog inputs can be added to any board using a Analog Multiplexer / Demultiplexer (50 cents per chip in the U.S.)...
http://www.arduino.cc/playground/learning/4051

[Reply #4 on:]

wow thank you very much , this is great because i got an uno and this could save me quite some bucks i could spend on other fancy ardu hardware.

Its says "can switch fast" between different pins, do you have an idea which range "fast" means?

Is there something like that also for digital pins? :-)

[Reply #5 on:]

wow thank you very much , this is great because i got an uno and this could save me quite some bucks i could spend on other fancy ardu hardware.

You are welcome.

Its says "can switch fast" between different pins, do you have an idea which range "fast" means?

I don't.  The datasheet is the best place to get answers for questions like that.

Is there something like that also for digital pins? :-)

I believe those chips will also work for digital inputs.  For digital outputs shift registers are a good choice.

[Reply #6 on:]

Its says "can switch fast" between different pins, do you have an idea which range "fast" means?

Is there something like that also for digital pins? :-)

The Nat Semi chip  states 500ns is typical switching time between pins.

If the chip allows analog signals it will always allow digital signals.

[Reply #7 on:]

The Nat Semi chip  states 500ns is typical switching time between pins.

With the AVR processor running at 16 MHz that would be 8 machine cycles.  A very very short delay after switching would be a good idea (_delay_us(0.5);).

[Reply #8 on:]

thank you!

sometimes i see code with like delay(1) delay(2) all over the place. whats the reason for that?
i read to avoid delay and use millis() instead.

i mean, in this case, ok it takes time to switch, so u want to wait a little bit. is that the only reason to use delay at all?

do you know if there r important differences between those 4051?
on ebay i find like  CD4051 Cmos, HC4051, HCF4051, CD4051BE

[Reply #9 on:]

thank you!

You are welcome!

sometimes i see code with like delay(1) delay(2) all over the place. whats the reason for that?

I assume for the same reason I proposed a delay: to give something time to change states.  But, without a context, I have no way to answer definitively.

i mean, in this case, ok it takes time to switch, so u want to wait a little bit.

It takes very very little time to switch; eight or fewer machine instructions.  The delay I suggested is three and a half orders of magnitude shorter than delay(1).

is that the only reason to use delay at all?

That's the only reason I would ever use delay.

do you know if there r important differences between those 4051?

I have no idea.  Someone else will have to help with that question.

[Reply #10 on:]

I don't think you can buy a "CD4051". Only CD4051B is available. The "E" specifies that it's a DIP package (not SOIC, etc.).

HC74 refers to the manufacturing method (a less modern method) of the chip logic. Typically these are limited to 5V signaling.

[Reply #11 on:]

thx both of you!

so with CD4051B i wont go wrong? as i like dip

that CD 4051 is actually called HEF4051BP (cmos, phillips)) and there is MC14051BCP, that HEF is actually the cheapest i find on ebay 24cents per piece.

is it ok, or bad?

http://www.ebay.de/itm/5-x-CMOS-4051-Multiplexer-8Kanal-analog-digital-DIP16-/310373781914?pt=Bauteile&hash=item4843b8119a

[Reply #12 on:]

thx both of you!

so with CD4051B i wont go wrong? as i like dip

that CD 4051 is actually called HEF4051BP (cmos, phillips)) and there is MC14051BCP, that HEF is actually the cheapest i find on ebay 24cents per piece.

is it ok, or bad?

http://www.ebay.de/itm/5-x-CMOS-4051-Multiplexer-8Kanal-analog-digital-DIP16-/310373781914?pt=Bauteile&hash=item4843b8119a

Hi

I used various "cd4051" dip type and they all functioning as same. But check and compare the datasheets for extra security.
This product is also useful: https://www.sparkfun.com/products/10680
You can get the IC in dip type too.