I2C在帶有Android Things的Raspberry Pi 3上不起作用

Question

如何發現問題？ 我正在嘗試在I2C總線上找到一台設備。 它找到了總線，但是沒有找到任何設備。 我有兩個主板，兩個不同的設備（AM2321和轉換器I2C-> 3wire），並嘗試了不同的組合。 我做錯了事，但無法理解，究竟是什么。

    val bus = manager.i2cBusList.first() // in my device one and only one bus now
    Log.d("happy", "bus: $bus")

    val devices = (0..127).filter { address ->
        manager.openI2cDevice(bus, address).use { device ->
            try {
                device.write(ByteArray(1), 1)
                true
            } catch (e: IOException) {
                false
            }
        }
    }

    if (devices.isEmpty()) {
        Log.d("happy", "no devices")
    } else {
        devices.forEach { address ->
            Log.d("happy", "device $address")
        }
    }

Answer 1

借助Android Things DP 6，您可以使用PIO CLI工具檢測問題：

 pio i2c name address subcommand [arg] name is the name of a valid I2C bus. address is the address of an I2C device. subcommand can be one of the following: Subcommand Description read-raw size Read size bytes from device. read-reg-byte reg Read a byte from reg. read-reg-word reg Read a word (2 bytes) from reg. read-reg-buffer reg size Read size bytes from reg. write-raw val [val ...] Write val to device. write-reg-byte reg val Write byte val to reg. write-reg-word reg val Write word val to reg. write-reg-buffer reg val [val ...] Write val to reg. 

例

 $ pio i2c I2C1 0x10 write-reg-byte 0x20 0x40 $ pio i2c I2C1 0x12 read-reg-byte 0x24 0x7F 

也看看這個和那個教程。