title: Can't connect to i.MX7 via fastboot
body: <p>I have an IMX7 board from TechNexion. This is the board linked from the Android Things website as a supported board. On unboxing the board, I cannot connect to the device via Fastboot. I can access the boot prompt and default/shipped linux installation via a serial connection. It also connects via ethernet. But no Fastboot. I'd like to install the latest Android Things OS.</p>
  
  <p><code>fastboot devices</code> returns nothing. <code>adb devices</code> returns nothing. Rebooting adb has no impact. I've also tried starting Fastboot from the U-Boot prompt.</p>
  
  <pre><code>=&gt; fastboot
  Unknown command 'fastboot' - try 'help'
  </code></pre>
  
  <p>The documentation implies it's installed on the device.</p>
  
  <p>I'm running the latest Android platform tools (26.0.0) on a Mac (10.12.6).</p>
  
  <p>I don't have much experience with Fastboot or hardware, but I have connected to a few other boards without any problem. Any ideas appreciated.</p>
  
  <p>EDIT: below is the output as seen from the serial connection. This is the bootloader output, and then also the initial part of the Linux boot sequence.</p>
  
  <pre><code>MMC:   FSL_SDHC: 0, FSL_SDHC: 1
  No panel detected: default to MCIMX28LCD
  Display: MCIMX28LCD (800x480)
  Video: 800x480x24
  In:    serial
  Out:   serial
  Err:   serial
  switch to partitions #0, OK
  mmc1(part 0) is current device
  Net:   FEC0
  Warning: FEC0 MAC addresses don't match:
  Address in SROM is         00:1f:7b:86:2e:3f
  Address in environment is  00:1f:7b:aa:01:32
  
  Normal Boot
  Hit any key to stop autoboot:  0 
  switch to partitions #0, OK
  mmc1(part 0) is current device
  switch to partitions #0, OK
  mmc1(part 0) is current device
  reading boot.scr
  ** Unable to read file boot.scr **
  reading zImage
  5726824 bytes read in 149 ms (36.7 MiB/s)
  Booting from mmc ...
  reading imx7d-pico_pi.dtb
  44004 bytes read in 17 ms (2.5 MiB/s)
  Kernel image @ 0x80800000 [ 0x000000 - 0x576268 ]
  ## Flattened Device Tree blob at 83000000
     Booting using the fdt blob at 0x83000000
     Using Device Tree in place at 83000000, end 8300dbe3
  
  Starting kernel ...
  
  Booting Linux on physical CPU 0x0
  Linux version 4.1.15-224683-gf3ba9d9 (tapani@triceratops) (gcc version 5.1.1 20150608 (Linaro GCC 5.1-2015.08) ) #4 SMP PREEMPT Tue Dec 20 17:50:41 HKT 2016
  </code></pre>