040000 tree 0b409d660574ee9bf362f5eaf30e8d5b3b087d3b	boot_serial
040000 tree 0909c9c27c218a91a5d5ee375dfbdaa9ee35f382	bootutil
040000 tree d54029431a871314bd0c39b047f8169ebbc733ea	mynewt
040000 tree b0eacbac7782abe9d671b0e5e6383a72f577f46c	zephyr