Looking for a Simple Basic Project for Beginner to learn
February 16, 2023, 19:20
I have a raspberry pi 4 here. I have a breadboard, some LEDs, some resistors, a button
I am looking for a simple beginner project, talk to me like I'm a 5 year old who can read with good documentation so that I can learn working with Raspberry Pi, creating something on a bread board, pin assignment and basic Python -> to get hardware to do something.
I know some Python - I can also look up things when I get a good base down
A little about breadboard LEDs but I'm not great - I was trying to get this stupid LED to light up and I did for a bit then it died.
I just would like a step by step project that I can see a positive result and then branch out from there.
Any suggestions would be appreciated.
actualy nvm. im no supposed to be sharing that stuff :(. ill point u at places
a pi board has this thing called "gpio" that stnads for general purpose io. thats how you get physical electrical signals from a pi
watch that you DONT FRY THE PI BECAUSE U HAVE THEWRONG VOLTAGES
the pins take around 3.3v although some take 5v. DO NOT INPUT 5V on a pin unless it specifically says it can take it
there a good chunck of features in the sys/class files
gpio is all that i really know about.
ill just go over bare bone use of the pins
note - there is a difference between gpio #'s and pin #'s
to send/receive signals from, say gpio17 (aka pin11), go to the "/sys/class/gpio" directory and type
echo 17 >> export
this will create a new folder called "gpio17" that will be how you control that gpio
go into the folder and youll see
to tell the pin to receive signals type
echo in >> direction, replace "in" with "out" if you want to send a signal
either way, to control/read the signal. read or write the file called "value" in that same directory
reminder that DO NOT PUT MORE THAN 3.3v TO THE PIN or u will fry the board. there is a saftey that shuts down the os if you do but its a last resort
safest practice would be to use the 3.3v power supply pin from the board
the gpio pin settings are removed when the pi restarts
receiving signal demo)
then type
watch -n .5 "echo "signal:"; cat ./gpio17/value"
now if u connect gpio #17 on your raspberry pi board to a power supply(preferably the 3.3v supply pin on the board) the bash thing will show "signal: 1" when ocnnected, 0 otherwise
the "watch" command is just the bash equivilent of a while loop. in this case, runs every .5 of a second and prints out ("signal: " + [whatever is read form the value file])
to send a signal from the pin echo "out" instead of "in" and write 0 or 1 to the value file.
heres some example functions in C to do what I just described in code
void gpioOutput(int pin)
{
FILE file;
char str[35];
file = fopen("/sys/class/gpio/export", "w");
fprintf(file, "%d", pin);
fclose(file);
sprintf(str, "/sys/class/gpio/gpio%d/direction", pin);
file = fopen(str, "w");
fprintf(file, "out");
fclose(file);
}
void gpioInput(int pin)
{
FILE file;
char str[35];
file = fopen("/sys/class/gpio/export", "w");
fprintf(file, "%d", pin);
fclose(file);
sprintf(str, "/sys/class/gpio/gpio%d/direction", pin);
file = fopen(str, "w");
fprintf(file, "in");
fclose(file);
}
void gpioWrite(int pin, int value)
{
FILE file;
char str[35];
sprintf(str, "/sys/class/gpio/gpio%d/value", pin);
file = fopen(str, "w");
fprintf(file, "%d", value);
fclose(file);
}
int gpioRead(int pin)
{
FILE file;
int result;
char str[30];
sprintf(str, "/sys/class/gpio/gpio%d/value", pin);
file = fopen(str, "rw");
fscanf(file, "%d", &result);
fclose(file);
return result;
}
opening and closing files as much as these funcitons do is not good pratice
these should be simple to translate to python (gooogle is your firend)
example of connecting the pi to a bread board and using gpio to turn leds on/off
also tip. if u dont have the desk space for both a desktop and raspPi set up suggest u just ssh on to the pi through the desktop. best done with puTTy. u can find your pi's ip address as one of the ones that appear as the output of this powershell script(windows only)
## Q:\Test\2017\01\21\SO_41785413.ps1
>> ## Ping subnet
>> $Subnet = "192.168."
>> 1..254|ForEach-Object{
>> Start-Process -WindowStyle Hidden ping.exe -Argumentlist "-n 1 -l 0 -f -i 2 -w 1 -4 $SubNet$_"
>> }
>> $Computers =(arp.exe -a | Select-String "$SubNet.dynam") -replace ' +',','|
>> ConvertFrom-Csv -Header Computername,IPv4,MAC,x,Vendor|
>> Select Computername,IPv4,MAC
>>
>> ForEach ($Computer in $Computers){
>> nslookup $Computer.IPv4|Select-String -Pattern "^Name:\s+([^\.]+).$"|
>> ForEach-Object{
>> $Computer.Computername = $_.Matches.Groups[1].Value
>> }
>> }
>> $Computers | Format-Table
>> #$Computers | Out-Gridview
- altered version of https://stackoverflow.com/questions/41785413/use-powershell-to-get-device-names-and-their-ipaddress-on-a-home-network
Awesome thank you this is a perfect start I'll go over - I appreciate it