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+# H3 Tiny AES128 in C
+
+This is a small portable (and slow?) implementation of AES128 in C.
+
+AES128 ECB is symmetric, so you use the same function for encrypting and decrypting.
+
+The module uses just a bit more than 200 bytes of RAM and 1K ROM when compiled for ARM.
+YMMV depending on target platform and optimization skills of your compiler.
+
+
+GCC size output when compiled for ARM:
+
+$ arm-none-eabi-gcc -Os -c aes.c -o aes.o
+$ size aes.o
+   text	   data	    bss	    dec	    hex	filename
+   1079	      0	    204	   1283	    503	aes.o
+
+
+
+$ arm-none-eabi-gcc --version
+arm-none-eabi-gcc (GNU Tools for ARM Embedded Processors) 4.8.3 20131129 (release) [ARM/embedded-4_8-branch revision 205641]
+Copyright (C) 2013 Free Software Foundation, Inc.
+This is free software; see the source for copying conditions.  There is NO
+warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+
+The implementation is verified against the data in National Institute of Standards and Technology Special Publication 800-38A 2001 ED.