Hello, I have connected a BMP280 pressure sensor to my piZeroW just to learn a little of i2c programming on NetBSD. Before doing real programming I issued a i2scan command to ensure the system works, but a lot of inexistent devices are detected (even if nothing is connected to the pi)
netbsd-raspaZeroW# i2cscan /dev/iic0 /dev/iic0: found device at 0x09 /dev/iic0: found device at 0x0a /dev/iic0: found device at 0x0b /dev/iic0: found device at 0x0d /dev/iic0: found device at 0x0e /dev/iic0: found device at 0x0f /dev/iic0: found device at 0x10 /dev/iic0: found device at 0x11 /dev/iic0: found device at 0x12 /dev/iic0: found device at 0x13 /dev/iic0: found device at 0x14 /dev/iic0: found device at 0x15 /dev/iic0: found device at 0x16 /dev/iic0: found device at 0x17 /dev/iic0: found device at 0x18 /dev/iic0: found device at 0x19 /dev/iic0: found device at 0x1a /dev/iic0: found device at 0x1b /dev/iic0: found device at 0x1c /dev/iic0: found device at 0x1d /dev/iic0: found device at 0x1e /dev/iic0: found device at 0x1f /dev/iic0: found device at 0x20 /dev/iic0: found device at 0x21 /dev/iic0: found device at 0x22 /dev/iic0: found device at 0x23 /dev/iic0: found device at 0x24 /dev/iic0: found device at 0x25 /dev/iic0: found device at 0x26 /dev/iic0: found device at 0x27 /dev/iic0: found device at 0x29 /dev/iic0: found device at 0x2a /dev/iic0: found device at 0x2b /dev/iic0: found device at 0x2c /dev/iic0: found device at 0x2d /dev/iic0: found device at 0x2e /dev/iic0: found device at 0x2f /dev/iic0: found device at 0x30 /dev/iic0: found device at 0x31 /dev/iic0: found device at 0x32 /dev/iic0: found device at 0x33 /dev/iic0: found device at 0x34 /dev/iic0: found device at 0x35 /dev/iic0: found device at 0x36 /dev/iic0: found device at 0x38 /dev/iic0: found device at 0x39 /dev/iic0: found device at 0x3a /dev/iic0: found device at 0x3b /dev/iic0: found device at 0x3c /dev/iic0: found device at 0x3d /dev/iic0: found device at 0x3e /dev/iic0: found device at 0x3f /dev/iic0: found device at 0x40 /dev/iic0: found device at 0x41 /dev/iic0: found device at 0x42 /dev/iic0: found device at 0x43 /dev/iic0: found device at 0x44 /dev/iic0: found device at 0x45 /dev/iic0: found device at 0x46 /dev/iic0: found device at 0x47 /dev/iic0: found device at 0x4c /dev/iic0: found device at 0x4d /dev/iic0: found device at 0x4e /dev/iic0: found device at 0x4f /dev/iic0: found device at 0x50 /dev/iic0: found device at 0x51 /dev/iic0: found device at 0x52 /dev/iic0: found device at 0x53 /dev/iic0: found device at 0x54 /dev/iic0: found device at 0x55 /dev/iic0: found device at 0x56 /dev/iic0: found device at 0x57 /dev/iic0: found device at 0x58 /dev/iic0: found device at 0x59 /dev/iic0: found device at 0x5a /dev/iic0: found device at 0x5b /dev/iic0: found device at 0x5c /dev/iic0: found device at 0x5d /dev/iic0: found device at 0x5e /dev/iic0: found device at 0x5f /dev/iic0: found device at 0x60 /dev/iic0: found device at 0x62 /dev/iic0: found device at 0x63 /dev/iic0: found device at 0x64 /dev/iic0: found device at 0x65 /dev/iic0: found device at 0x66 /dev/iic0: found device at 0x67 /dev/iic0: found device at 0x68 /dev/iic0: found device at 0x69 /dev/iic0: found device at 0x6a /dev/iic0: found device at 0x6b /dev/iic0: found device at 0x6c /dev/iic0: found device at 0x6d /dev/iic0: found device at 0x6e /dev/iic0: found device at 0x6f /dev/iic0: found device at 0x70 /dev/iic0: found device at 0x71 /dev/iic0: found device at 0x72 /dev/iic0: found device at 0x73 /dev/iic0: found device at 0x74 /dev/iic0: found device at 0x75 /dev/iic0: found device at 0x76 /dev/iic0: found device at 0x77 /dev/iic0: 103 devices found netbsd-raspaZeroW# i2cscan /dev/iic1 /dev/iic1: found device at 0x09 /dev/iic1: found device at 0x0a /dev/iic1: found device at 0x0b /dev/iic1: found device at 0x0d /dev/iic1: found device at 0x0e /dev/iic1: found device at 0x0f /dev/iic1: found device at 0x10 /dev/iic1: found device at 0x11 /dev/iic1: found device at 0x12 /dev/iic1: found device at 0x13 /dev/iic1: found device at 0x14 /dev/iic1: found device at 0x15 /dev/iic1: found device at 0x16 /dev/iic1: found device at 0x17 /dev/iic1: found device at 0x18 /dev/iic1: found device at 0x19 /dev/iic1: found device at 0x1a /dev/iic1: found device at 0x1b /dev/iic1: found device at 0x1c /dev/iic1: found device at 0x1d /dev/iic1: found device at 0x1e /dev/iic1: found device at 0x1f /dev/iic1: found device at 0x20 /dev/iic1: found device at 0x21 /dev/iic1: found device at 0x22 /dev/iic1: found device at 0x23 /dev/iic1: found device at 0x24 /dev/iic1: found device at 0x25 /dev/iic1: found device at 0x26 /dev/iic1: found device at 0x27 /dev/iic1: found device at 0x29 /dev/iic1: found device at 0x2a /dev/iic1: found device at 0x2b /dev/iic1: found device at 0x2c /dev/iic1: found device at 0x2d /dev/iic1: found device at 0x2e /dev/iic1: found device at 0x2f /dev/iic1: found device at 0x30 /dev/iic1: found device at 0x31 /dev/iic1: found device at 0x32 /dev/iic1: found device at 0x33 /dev/iic1: found device at 0x34 /dev/iic1: found device at 0x35 /dev/iic1: found device at 0x36 /dev/iic1: found device at 0x38 /dev/iic1: found device at 0x39 /dev/iic1: found device at 0x3a /dev/iic1: found device at 0x3b /dev/iic1: found device at 0x3c /dev/iic1: found device at 0x3d /dev/iic1: found device at 0x3e /dev/iic1: found device at 0x3f /dev/iic1: found device at 0x40 /dev/iic1: found device at 0x41 /dev/iic1: found device at 0x42 /dev/iic1: found device at 0x43 /dev/iic1: found device at 0x44 /dev/iic1: found device at 0x45 /dev/iic1: found device at 0x46 /dev/iic1: found device at 0x47 /dev/iic1: found device at 0x4c /dev/iic1: found device at 0x4d /dev/iic1: found device at 0x4e /dev/iic1: found device at 0x4f /dev/iic1: found device at 0x50 /dev/iic1: found device at 0x51 /dev/iic1: found device at 0x52 /dev/iic1: found device at 0x53 /dev/iic1: found device at 0x54 /dev/iic1: found device at 0x55 /dev/iic1: found device at 0x56 /dev/iic1: found device at 0x57 /dev/iic1: found device at 0x58 /dev/iic1: found device at 0x59 /dev/iic1: found device at 0x5a /dev/iic1: found device at 0x5b /dev/iic1: found device at 0x5c /dev/iic1: found device at 0x5d /dev/iic1: found device at 0x5e /dev/iic1: found device at 0x5f /dev/iic1: found device at 0x60 /dev/iic1: found device at 0x62 /dev/iic1: found device at 0x63 /dev/iic1: found device at 0x64 /dev/iic1: found device at 0x65 /dev/iic1: found device at 0x66 /dev/iic1: found device at 0x67 /dev/iic1: found device at 0x68 /dev/iic1: found device at 0x69 /dev/iic1: found device at 0x6a /dev/iic1: found device at 0x6b /dev/iic1: found device at 0x6c /dev/iic1: found device at 0x6d /dev/iic1: found device at 0x6e /dev/iic1: found device at 0x6f /dev/iic1: found device at 0x70 /dev/iic1: found device at 0x71 /dev/iic1: found device at 0x72 /dev/iic1: found device at 0x73 /dev/iic1: found device at 0x74 /dev/iic1: found device at 0x75 /dev/iic1: found device at 0x76 /dev/iic1: found device at 0x77 /dev/iic1: 103 devices found netbsd-raspaZeroW# i2cscan /dev/iic2 /dev/iic2: found device at 0x09 /dev/iic2: found device at 0x0a /dev/iic2: found device at 0x0b /dev/iic2: found device at 0x0d /dev/iic2: found device at 0x0e /dev/iic2: found device at 0x0f /dev/iic2: found device at 0x10 /dev/iic2: found device at 0x11 /dev/iic2: found device at 0x12 /dev/iic2: found device at 0x13 /dev/iic2: found device at 0x14 /dev/iic2: found device at 0x15 /dev/iic2: found device at 0x16 /dev/iic2: found device at 0x17 /dev/iic2: found device at 0x18 /dev/iic2: found device at 0x19 /dev/iic2: found device at 0x1a /dev/iic2: found device at 0x1b /dev/iic2: found device at 0x1c /dev/iic2: found device at 0x1d /dev/iic2: found device at 0x1e /dev/iic2: found device at 0x1f /dev/iic2: found device at 0x20 /dev/iic2: found device at 0x21 /dev/iic2: found device at 0x22 /dev/iic2: found device at 0x23 /dev/iic2: found device at 0x24 /dev/iic2: found device at 0x25 /dev/iic2: found device at 0x26 /dev/iic2: found device at 0x27 /dev/iic2: found device at 0x29 /dev/iic2: found device at 0x2a /dev/iic2: found device at 0x2b /dev/iic2: found device at 0x2c /dev/iic2: found device at 0x2d /dev/iic2: found device at 0x2e /dev/iic2: found device at 0x2f /dev/iic2: found device at 0x30 /dev/iic2: found device at 0x31 /dev/iic2: found device at 0x32 /dev/iic2: found device at 0x33 /dev/iic2: found device at 0x34 /dev/iic2: found device at 0x35 /dev/iic2: found device at 0x36 /dev/iic2: found device at 0x38 /dev/iic2: found device at 0x39 /dev/iic2: found device at 0x3a /dev/iic2: found device at 0x3b /dev/iic2: found device at 0x3c /dev/iic2: found device at 0x3d /dev/iic2: found device at 0x3e /dev/iic2: found device at 0x3f /dev/iic2: found device at 0x40 /dev/iic2: found device at 0x41 /dev/iic2: found device at 0x42 /dev/iic2: found device at 0x43 /dev/iic2: found device at 0x44 /dev/iic2: found device at 0x45 /dev/iic2: found device at 0x46 /dev/iic2: found device at 0x47 /dev/iic2: found device at 0x4c /dev/iic2: found device at 0x4d /dev/iic2: found device at 0x4e /dev/iic2: found device at 0x4f /dev/iic2: found device at 0x50 /dev/iic2: found device at 0x51 /dev/iic2: found device at 0x52 /dev/iic2: found device at 0x53 /dev/iic2: found device at 0x54 /dev/iic2: found device at 0x55 /dev/iic2: found device at 0x56 /dev/iic2: found device at 0x57 /dev/iic2: found device at 0x58 /dev/iic2: found device at 0x59 /dev/iic2: found device at 0x5a /dev/iic2: found device at 0x5b /dev/iic2: found device at 0x5c /dev/iic2: found device at 0x5d /dev/iic2: found device at 0x5e /dev/iic2: found device at 0x5f /dev/iic2: found device at 0x60 /dev/iic2: found device at 0x62 /dev/iic2: found device at 0x63 /dev/iic2: found device at 0x64 /dev/iic2: found device at 0x65 /dev/iic2: found device at 0x66 /dev/iic2: found device at 0x67 /dev/iic2: found device at 0x68 /dev/iic2: found device at 0x69 /dev/iic2: found device at 0x6a /dev/iic2: found device at 0x6b /dev/iic2: found device at 0x6c /dev/iic2: found device at 0x6d /dev/iic2: found device at 0x6e /dev/iic2: found device at 0x6f /dev/iic2: found device at 0x70 /dev/iic2: found device at 0x71 /dev/iic2: found device at 0x72 /dev/iic2: found device at 0x73 /dev/iic2: found device at 0x74 /dev/iic2: found device at 0x75 /dev/iic2: found device at 0x76 /dev/iic2: found device at 0x77 /dev/iic2: 103 devices found netbsd-raspaZeroW# I also configured config.txt file (added last line): netbsd-raspaZeroW# cat /boot/config.txt # upstream_kernel=1 os_prefix=dtb/ cmdline=../cmdline.txt # UART settings, see https://www.raspberrypi.com/documentation/computers/configuration.html#configuring-uarts enable_uart=1 force_turbo=0 # Default kernel for BCM2836 and later kernel=/kernel7.img # Override kernel for BCM2835 based boards [pi0] kernel=/kernel.img [pi0w] kernel=/kernel.img [pi1] kernel=/kernel.img [all] # dtparam=i2c_arm=on netbsd-raspaZeroW# But the result is the same. Am I missing something? Thanks so much. Ramiro.