Raspberry Pi Pico

Raspberry Pi Pico is a low-cost, high-performance microcontroller board with flexible digital interfaces.

Raspberrypi pico design files

raspberry pi pico pinout

pinout and design files

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Run-Reset button (right side)

To help set mass storage with BOOTSEL + RUN-Reset button

Connect with micro-usb

Click on BOOTSEL button to enable mass storage

   1 sudo dmesg
   2 # [ 3570.065996] usb 1-4.3: Product: RP2 Boot
   3 # [ 3570.066006] usb 1-4.3: Manufacturer: Raspberry Pi
   4 # [ 3570.066016] usb 1-4.3: SerialNumber: E0C9xxxxxxxx
   5 # [ 3570.163372] usb-storage 1-4.3:1.0: USB Mass Storage device detected
   6 # [ 3570.164049] scsi host2: usb-storage 1-4.3:1.0
   7 # [ 3570.164381] usbcore: registered new interface driver usb-storage
   8 # [ 3570.180142] usbcore: registered new interface driver uas
   9 # [ 3571.192940] scsi 2:0:0:0: Direct-Access     RPI      RP2              3    PQ: 0 ANSI: 2
  10 # [ 3571.194468] sd 2:0:0:0: Attached scsi generic sg1 type 0
  11 # [ 3571.195164] sd 2:0:0:0: [sdb] 262144 512-byte logical blocks: (134 MB/128 MiB)
  12 # [ 3571.195818] sd 2:0:0:0: [sdb] Write Protect is off
  13 # [ 3571.195830] sd 2:0:0:0: [sdb] Mode Sense: 03 00 00 00
  14 # [ 3571.196325] sd 2:0:0:0: [sdb] No Caching mode page found
  15 # [ 3571.196335] sd 2:0:0:0: [sdb] Assuming drive cache: write through
  16 # [ 3571.217448]  sdb: sdb1
  17 # [ 3571.237585] sd 2:0:0:0: [sdb] Attached SCSI removable disk
  18

Serial USB ttyACM0

   1 sudo dmesg
   2 # [9067045.808125] usb 1-1.3: new full-speed USB device number 7 using dwc_otg
   3 # [9067045.941554] usb 1-1.3: New USB device found, idVendor=2e8a, idProduct=000a, bcdDevice= 1.00
   4 # [9067045.941564] usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
   5 # [9067045.941568] usb 1-1.3: Product: Pico
   6 # [9067045.941572] usb 1-1.3: Manufacturer: Raspberry Pi
   7 # [9067045.941577] usb 1-1.3: SerialNumber: E661xxxxxxxxxxxx
   8 # [9067045.944106] cdc_acm 1-1.3:1.0: ttyACM0: USB ACM device
   9 apt install picocom 
  10 picocom -b 115200 --echo /dev/ttyACM0 
  11 # on
  12 # Led is ON 5
  13 # Periodical timer at 4238154004018
  14 # on
  15 # Led is ON 5
  16 # off
  17 # Led is OFF 5
  18 # on
  19 # Led is ON 5
  20 # Periodical timer at 4238164004155
  21 # gp21on
  22 # GP21 is ON
  23 # ctrl+a , ctrl+x
  24 # Thanks for using picocom
  25

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ADC2 GP28 PIN34 (hello_adc.c)

https://github.com/raspberrypi/pico-examples/blob/master/adc/hello_adc/hello_adc.c

   1 adc_init()
   2 adc_gpio_init(28)
   3 adc_select_input(2)
   4 uint16_t res = adc_read()
   5 conversion_factor = 3.3f/(1<<12)

ADC4 onboard temperature sensor (onboard_temperature.c)

In the section 4.9. ADC and Temperature Sensor available in rp2040 datasheet it's mentioned that ADC4 reads values from an onboard temperature sensor.

onboard_temperature.c

   1 adc_init()
   2 adc_set_temp_sensor_enabled(true)
   3 adc_select_input(4)
   4 uint16_t res = adc_read()
   5 conversion_factor = 3.3f/(1<<12)

/etc/rc.local in Raspbian to init ttyACM0

   1 #!/bin/sh -e
   2 /usr/bin/logger "Initialize port ttyACMO for raspberry pico"
   3 chmod 666 /dev/ttyACM0
   4 stty -F /dev/ttyACM0 raw speed 115200 -crtscts cs8 -parenb -cstopb
   5 exit 0

NTC Thermistor

1 kΩ NTC Sensor, 500 mW power and material constant 3600K, temperature range between -55°C and 125°C with diameter of 6.5 mm. At 25°C has resistance of 1 kΩ.

The relationship between temperature and resistance for an NTC thermistor is non-linear.