This guide and scripts are based on the excelent work made by https://github.com/Thore-Krug/Flash-CHIP and the guide in https://gist.github.com/luzhuomi/526fbcc30f3522f09eacf20d0f776fa5

1. Remove the C.H.I.P. from its case (in case you have a Pocket C.H.I.P.).
2. Connect the FEL and a GROUND pin of the C.H.I.P. (for example, with a paperclip).
3. Connect the C.H.I.P. its micro USB port to a USB port of your Linux machine. Make sure that the port and cable allow for plenty of power. If you get a FEL error, it may be because the C.H.I.P. is running under-voltage.
4. On the Linux machine:
   • run git clone https://github.com/asophila/Flash-CHIP.git to clone this repository
   • cd into the location where you stored this repository
   • run sudo chmod x Flash.sh
   • run ./Flash.sh
   • Select the version you want to install
   • Wait until the installation finishes

1. Remove the FEL connection (the paperclip)
2. Unplug 3 seconds
3. Plug the C.H.I.P. again
4. Connect to the chip using sudo screen /dev/ttyACM0
5. Use user: chip and password: chip to connect
6. run sudo nmtui to set-up a wifi connection to YOUR_SSID
7. run sudo nmcli c to show your current connections
8. run sudo nmcli c m <YOUR SSID> connection.autoconnect yes to set autoconnection to YOUR_SSID wifi in case of trouble
9. use ip addr | grep "inet " | awk 'NR==2{print $2}' | cut -d/ -f1 to get your CHIP_IP. From your linux computer open other terminal and connect using ssh chip@CHIP_IP. You can close the terminal running screen.

1. run sudo su - to allow all the next changes as superuser
2. run bash <(curl -s https://raw.githubusercontent.com/asophila/Flash-CHIP/master/CHIP-updater/jessie-to-stretch.sh) to update from Debian Jessie to Debian Stretch
3. reboot C.H.I.P. into Debian Stretch

1. From your linux computer open other terminal and connect using ssh chip@<CHIP IP>.
2. run sudo su - to allow all the next changes as superuser
3. run bash <(curl -s https://raw.githubusercontent.com/asophila/Flash-CHIP/master/CHIP-updater/stretch-to-buster.sh) to update from Debian Stretch to Debian Buster
4. reboot C.H.I.P. into Debian Buster