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--- a/README.md
+++ b/README.md
@@ -1,5 +1,11 @@
 # micro-sci-a2-controller
 
+This is a clone of the Micro-SCI / Franklin floppy drive controller.
+
+v0.1 is a direct clone, reverse-engineered from a Micro-SCI board.  It was cross-checked with a Franklin-branded board, as well as the (belatedly discovered) official Franklin schematic (included in doc/service_and_schematics.pdf)
+
+Firmware images can be built via the Makefile in the firmware subdirectory.  The build framework requires cc65.
+
 ![usci](usci.png?raw=true "usci")
 
 ## Jumper block