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+# Obligatory blinky for the 5A-75E
+
+This quick-and-dirty design blinks the green user LED on the Colorlight 5A-75E
+at 1 Hz with a 50% duty. It divides the 25 MHz crystal oscillator input to the
+FPGA down with a counter to achieve this.
+
+## Notes
+
+I've seen one of the HC245s decide to oscillate if you flash this bitstream
+after letting the factory design start. It tried to draw my current limit of
+500 mA, and would presumably draw more if allowed. It's probably due to this
+design leaving unused I/Os in high-Z. It seems not to be able to get itself
+into the state when I set a lower current limit and/or a lower voltage on the
+board's main input, such as 300 mA and/or 3.3 V.
+
+Another workaround is not to load the factory design boot up.
+