I really need 4 GNDs pins in my arudino and there are LOTS of alternativas in the internet and I found one very interesting: if I take a digital pin and do :
pinMode(4,OUTPUT);
digitalWrite(4,LOW);
People say this will make the digital pin 4 become a GND pin just like any other regular GND pin at arduino. Will this cause any problem to my arduino? Burn it in the long time?
I wouldn't do that, for at least 2 reasons :
It won't be a physical GND - there are some components inside the chip (which allow it to be Input or Output and in different states), between the input and 0V , they don't disappear when the pin is in LOW state -> your pseudo-GND won't be a good one
what happens if, by mistake, you put that pin in HIGH state in the sketch ? :o
What is your project situation? Using a 'breadboard' without power buses? (If so, just run a wire from GND to one of the breadboard rows - and you have 4 more Gnd points.)
[What's the market for a "Ground Shield"?]
batata004:
I really need 4 GNDs pins in my arudino and there are LOTS of alternativas in the internet and I found one very interesting: if I take a digital pin and do :pinMode(4,OUTPUT);
digitalWrite(4,LOW);People say this will make the digital pin 4 become a GND pin just like any other regular GND pin at arduino. Will this cause any problem to my arduino? Burn it in the long time?
Those people are wrong, you won't have anything like a good ground, and it will burn out if you
take any significant current.
Impedance between physical ground pins on Arduino - measured in fractions of an ohm,
impedance of an output pin - many dozens of ohms, limited to 40mA absolute max, or a fraction
of a mA if the Arduino is powered off...
Its not uncommon for people here to fail to understand the difference between a logic signal and
a power supply pin. ground is one power supply pin, a logic output is only for signalling or driving
light loads like one LED (some Arduino boards can't even drive a standard LED, though the Uno
and many others can).
Power and signal are not interchangable.
Takes wire from one ground pin, and twist two ground wires you need to that ground wire, problemo solvederado'd
Twisting(*) does not make reliable connections, that's well worth avoiding unless you
enjoy unreliable and random circuit behaviour.
(*) unless its proper wire-wrap forming a gas-tight weld.
thnks I will twist the wires together
MarkT:
Twisting(*) does not make reliable connections, that's well worth avoiding unless you
enjoy unreliable and random circuit behaviour.(*) unless its proper wire-wrap forming a gas-tight weld.
Twisting does fine... Provided you twist correctly. Not going to last forever, but long enough.
MarkT:
unless you
enjoy unreliable and random circuit behaviour.
Live a little.
Why not solder after twisting the wires? Soldering two wires together a is dead easy and can be done using even a garbage soldering iron (ie, the crappy non-temp controlled ones that trash circuit boards if you try to use them for board work - those are fine for soldering wires)
Soldering is a good idea, if you have a soldering iron...
Maybe you can connect an adapter header thing to the ICSP port and create a heap of grounds from the GND pin of the ICSP port. There are TWO different ICSP ports (on UNO and 2560), each with a GND pin.
Or use strong glue to glue a 90 degrees header/connector to a sizeable blue area of the arduino board ....... use very strong sturdy glue. Or spot weld a metal casing to the side of the metal USB casing ..... and insert plastic header socket into the casing. And use that extra header for grounds.
thnks I will twist the wires together
Have you ever heard of BUTT CONNECTORS ?