> There's the first 10.  Anybody else got additions?

ad 3: The fact that leaving RB3 floating does no harm on some chips (when
the moon is right) should not be taken as proof that holding the pin low is
not needed in geneal. And note that 16f62x's uses RB4 as LVP enable.

- At power-up the F87x's default to analog inputs for some port a pins. You
must disable the analog function to use these pins as discrete (digital)
input. Might be the case for other types too?

- beware of SUBLW and SUBWF. Contrary to what you could expect from an
accumulator-architecture these instructions substract W from something, not
something from W. The SUBLW (Substract Literfal from W) menemonic reflects
this, the SUBWF mnemonic was especially choosen to confuse you.

- beware of SUBLW and SUBWF. Take a good look at the instruction description
to see how the carry is set, it might not agree with what you expect!

- The OPTION instruction can - on the chips that support it! - be used
without any problem. Microchip is not suddenly gona drop this instruction
from an existing chip. The comment in the manuals should be understood as
stating that it might wel be dropped from FUTURE 14-bit core chips. So if
you want to have maximum code portability avoid OPTION, otherwise just use
it.

- When you have programmed your first PIC with with a blinking LED and it
blinks at a rate that you did not expect and no matter what you change the
blinking stays at that rate check whether you have disabled the watchdog.

- When you have programmed your first PIC with with a blinking LED no matter
what you change the LED stays on you might well be blinking the LED at a
very high rate. To check: connect it the other way round (to VCC instead of
GND or vice versa).

- The best way to kill a PIC is to connect the VCC/GND backwards. When this
is not your aim you might consider putting the PIC in a (round pin) socket
and solder an anti-parallel diode across the GND/VCC pins. Make sure that
the combo can still be put in a (flat pin) socket. This arrangement also
protects you against broken PIC pins.

- When your program worked OK in a windowed chip but fails in an OTP (or the
other way round), or your windowed chips fails in bright light (or in total
darkness, or the other way round)  you might have uninitialized variables.
Cover the windowed chip with something  REALLY black (not just UV-black) and
it should behave like an OTP. The metallic-like things used to make 5.25
inch floppies write-protected are reported to work quite well.

my 0.01 euro
Wouter

PS this list MUST be put on techref!

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