[Lancelot] Something to watch out for...
H. Peter Anvin
hpa at zytor.com
Tue Sep 21 12:47:12 PDT 2004
I just managed to get bitten by this -- perhaps I'm the only one -- so
here is a warning:
At least on the Cyclone edition board, the power to the CompactFlash
slot is gated!
I hadn't put cf_power in the pinlist I published ages ago, and as a
result it was left floating. The bizarre result was that the CF card
worked for reading, but not for writing! I guess there was just enough
power let through that the capacitors held Vcc high enough to work
(presumably above 3.2 V or so) except when it was writing.
It was a real puzzler to figure out.
Instantiating cf_power (pin M13) and driving it to VCC (1) solved the
I have uploaded an updated pin list to:
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