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+## v2.0 - "kajetanless" white PCB
+### #1: Programming header J6 has non-standard layout
+Use a custom cable.
+
+### #2: R1 reset line resistor is pull-down
+R1 footprint *shall not be populated*, and an equivalent resistor should be put
+in a pull-up configuration between reset line and ground.
+
+Sensible place for that is between one C2 leg and reset line going next to it
+to J6 programming header.
+
+## v2.1 - "pulled-up" green PCB
+Errata #2 fixed.