If you want to make portable Air quality sensor this is very easy setup. Make sure to include you mobile hostspot wifi ssid so that you can easily collect data from anywhere on the go.
Gas sensor normal takes 2-3 min to normalized it’s output vaules.
VCC = 3v3(OUT) - GP36
GND = GND -GP38
Input = ADC0 - GP26import network
import urequests
import machine
import time
import ubinascii
#only needed if sending over public ip with https.
USERNAME_P = "basic-auth-username"
PASSWORD_P = 'basic-auth-pass'
# WiFi Credentials
SSID = 'WIFI-SSID'
PASSWORD = 'WIFI-PASSWORD'
# PushGateway Configuration
PUSHGATEWAY_URL = 'https://pushgateway.example.com/metrics/job/gas_sensor/instance/pico-1/sensor/mq135'
# ADC Setup for MQ-135 on GP26 (ADC0)
adc = machine.ADC(26)
def connect_wifi():
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
if not wlan.isconnected():
print('Connecting to WiFi...')
wlan.connect(SSID, PASSWORD)
while not wlan.isconnected():
time.sleep(0.5)
print('Connected, IP:', wlan.ifconfig()[0])
def read_gas_sensor():
raw_value = adc.read_u16() # 0–65535
voltage = raw_value * 3.3 / 65535 # Convert to voltage if needed
return raw_value, voltage
def send_to_pushgateway(value):
# Prometheus format (you can include labels if you want)
payload = f"gas_sensor_value {value}\n"
auth_string = "{}:{}".format(USERNAME_P, PASSWORD_P)
auth_encoded = ubinascii.b2a_base64(auth_string.encode()).decode().strip()
headers = {
"Content-Type": "text/plain",
"Authorization": "Basic " + auth_encoded
}
try:
res = urequests.post(PUSHGATEWAY_URL, data=payload, headers=headers, timeout=5)
print("Pushed to gateway:", res.status_code)
res.close()
except Exception as e:
print("Push failed:", e)
def main():
connect_wifi()
while True:
raw, voltage = read_gas_sensor()
print(f"Gas Sensor Raw: {raw} | Voltage: {voltage:.3f}V")
send_to_pushgateway(raw)
time.sleep(1) # Push every 10 seconds
main()
#find device
dmesg | grep tty
$ read X < /dev/ttyACM0
hello
$ echo $X
Gas Sensor Raw: 2496 | Voltage: 0.126Vscreen /dev/ttyACM0
#with Baud rate
screen /dev/ttyACM0 9600apt install iperf3
#on server 192.168.0.10
iperf -s
#on client
iperf -c 192.168.0.10
root@lp-arm-3:~# iperf3 -c 192.168.0.10
Connecting to host 192.168.0.10, port 5201
[ 5] local 192.168.0. port 50976 connected to 192.168.0.10
port 5201
[ ID] Interval Transfer Bitrate Retr Cwnd
[ 5] 0.00-1.00 sec 11.4 MBytes 95.6 Mbits/sec 248 48.1 KBytes
[ 5] 1.00-2.00 sec 10.9 MBytes 91.2 Mbits/sec 260 38.2 KBytes
[ 5] 2.00-3.00 sec 10.9 MBytes 91.7 Mbits/sec 251 38.2 KBytes
[ 5] 3.00-4.00 sec 11.2 MBytes 93.8 Mbits/sec 245 48.1 KBytes
[ 5] 4.00-5.00 sec 10.8 MBytes 90.7 Mbits/sec 277 36.8 KBytes
[ 5] 5.00-6.00 sec 11.3 MBytes 94.9 Mbits/sec 247 38.2 KBytes
[ 5] 6.00-7.00 sec 11.1 MBytes 92.8 Mbits/sec 231 52.3 KBytes
[ 5] 7.00-8.00 sec 10.9 MBytes 91.7 Mbits/sec 260 46.7 KBytes
[ 5] 8.00-9.00 sec 10.8 MBytes 90.7 Mbits/sec 241 50.9 KBytes
[ 5] 9.00-10.00 sec 10.9 MBytes 91.7 Mbits/sec 245 46.7 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-10.00 sec 110 MBytes 92.5 Mbits/sec 2505 sender
[ 5] 0.00-10.05 sec 110 MBytes 91.9 Mbits/sec receiver
iperf Done.
Ref- https://www.jeffgeerling.com/blog/2025/exploring-wifi-7-2-gbps-on-raspberry-pi-5
git clone https://github.com/adafruit/Adafruit_Python_DHT.git
cd Adafruit_Python_DHT
if [ $(cat /proc/cpuinfo | grep Hardware | wc -l) != "1" ] ; then
cat /proc/cpuinfo > /etc/cpuinfo
echo -e "\nHardware : BCM2709" >> /etc/cpuinfo
mount --bind /etc/cpuinfo /proc/cpuinfo
echo "Mounted cpuinfo with Hardware info"
fi
python3 setup.py install
#!/bin/bash
cpu=$(</sys/class/thermal/thermal_zone6/temp)
cpu_temp=$(echo "$cpu/1000" | /usr/bin/bc -l)
echo "CPU_temp $cpu_temp"root@lp-knode-2:~# cat /sys/class/thermal/thermal_zone*/type
INT3400 Thermal
SEN1
SEN2
SEN3
SEN4
SEN5
pch_cannonlake
B0D4
iwlwifi_1
x86_pkg_temp
root@lp-knode-2:~# cat /sys/class/thermal/thermal_zone*/temp
20000
41050
47050
41050
45050
50
54000
46050
48000
46000https://askubuntu.com/questions/1110943/what-do-the-different-thermal-zones-actually-correspond-to
grdctl status
grdctl rdp enable
grdctl rdp set-credentials username pass
grdctl --system status --show-credentials
#connect
rdesktop -u USERNAME -p PASS 192.168.0.210
https://help.ubuntu.com/community/WakeOnLan
apt install ethtool
ethtool eth
root@home:/home# ethtool enp3s0
Settings for enp3s0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Speed: Unknown!
Duplex: Unknown! (255)
Auto-negotiation: on
master-slave cfg: preferred slave
master-slave status: unknown
Port: Twisted Pair
PHYAD: 0
Transceiver: external
MDI-X: Unknown
Supports Wake-on: pumbg
Wake-on: g
Link detected: no
wol p|u|m|b|a|g|s|d...
Sets Wake-on-LAN options. Not all devices support this.
The argument to this option is a string of characters speci‐
fying which options to enable.
p Wake on PHY activity
u Wake on unicast messages
m Wake on multicast messages
b Wake on broadcast messages
a Wake on ARP
g Wake on MagicPacket™
s Enable SecureOn™ password for MagicPacket™
d Disable (wake on nothing). This option
clears all previous options.
wake command
apt install etherwake
etherwake MAC-ADDRESSlsusb
ls /sys/bus/usb/devicesecho disabled | sudo tee /sys/bus/usb/devices/usb2/power/wakeupecho suspend | sudo tee /sys/bus/usb/devices/usb2/power/levelecho auto | sudo tee /sys/bus/usb/devices/usb2/power/levelLet me recap for Linux >= 2.6.38: The file power/level is deprecated now; use power/control instead. (power/wakeup is ok.)
https://stackoverflow.com/questions/4702216/controlling-a-usb-power-supply-on-off-with-linux
apt install powertop
powertopRSYNC_ENABLE=inetd
#install
apt-get -y install xinetdservice rsync
{
disable = no
socket_type = stream
wait = no
user = root
server = /usr/bin/rsync
server_args = --daemon
log_on_failure += USERID
flags = IPv4
}max connections = 2
log file = /var/log/rsync.log
timeout = 300
[share]
comment = Public Share
path = /home/share
read only = no
list = yes
uid = 0
gid = 0
auth users = user
secrets file = /etc/rsyncd.secretscat /etc/rsyncd.secrets
user1:user1
chmod 600 /etc/rsyncd.secrets/etc/init.d/xinetd restarthome@home:~$ rsync user1@192.168.29.142::share
Password:
drwxr-xr-x 4,096 2025/03/21 11:21:47 .
-rw-r--r-- 0 2025/03/21 11:21:47 1.txt
systemctl status bluetooth.service
● bluetooth.service - Bluetooth service
Loaded: loaded (/usr/lib/systemd/system/bluetooth.service; enabled; preset: enabled)
Active: active (running) since Fri 2025-03-21 07:57:38 IST; 1min 18s ago
Docs: man:bluetoothd(8)
Main PID: 21633 (bluetoothd)
Status: "Running"
Tasks: 1 (limit: 76673)
Memory: 1.1M (peak: 1.6M)
CPU: 55ms
CGroup: /system.slice/bluetooth.service
└─21633 /usr/libexec/bluetooth/bluetoothd
#!/bin/bash
if [[ $(hcitool con | grep '00:1B:66:0F:XX:XX' | wc -l) != 1 ]]
then
echo "connect 00:1B:66:0F:XX:XX" | bluetoothctl
else
echo "Already connected to 00:1B:66:0F:XX:XX"
firoot@home:~# bluetoothctl
bluetooth]# [NEW] Device F4:C8:8A:7F:xx:xx CP250003
[bluetooth]# hci0 type 7 discovering off
[bluetooth]# hci0 type 7 discovering on
[bluetooth]# hci0 type 7 discovering off
[bluetooth]# hci0 type 7 discovering on
[bluetooth]# [DEL] Device F4:C8:8A:7F:xx:xx CP250003
[bluetooth]# [NEW] Device F4:C8:8A:7F:xx:xx CP250003
[bluetooth]# hci0 type 7 discovering off
[bluetooth]# hci0 type 7 discovering on
[bluetooth]# [CHG] Device D0:49:7C:8F:xx:xx RSSI: 0xffffffab (-85)
list List available controllers
show [ctrl] Controller information
select <ctrl> Select default controller
devices [Paired/Bonded/Trusted/Connected] List available devices, with an optional property as the filter
system-alias <name> Set controller alias
reset-alias Reset controller alias
power <on/off> Set controller power
pairable <on/off> Set controller pairable mode
discoverable <on/off> Set controller discoverable mode
discoverable-timeout [value] Set discoverable timeout
agent <on/off/auto/capability> Enable/disable agent with given capability
default-agent Set agent as the default one
advertise <on/off/type> Enable/disable advertising with given type
set-alias <alias> Set device alias
scan <on/off/bredr/le> Scan for devices
info [dev/set] Device/Set information
pair [dev] Pair with device
cancel-pairing [dev] Cancel pairing with device
trust [dev] Trust device
untrust [dev] Untrust device
block [dev] Block device
unblock [dev] Unblock device
remove <dev> Remove device
connect <dev> Connect device
disconnect [dev] Disconnect device
menu <name> Select submenu
version Display version
quit Quit program
exit Quit program
help Display help about this program
export Print environment variables