It was certainly a good idea, but also always a suspect of
malfunctions and as such, almost never used. Newer code
organisation moves most of the code behind it to dda_clock()
anyways, so it also became mostly obsolete.
Rest In Peace, STEP_INTERRUPT_INTERRUPTIBLE, you were matter
of quite a number of interesting discussions and investigations.
Changes for Configtool by jbernardis <jeff.bernardis@gmail.com>
Eventual debugging LEDs aren't part of the CPU, but part of the
electronics. Accordingly, define it in config.*.h, not in
arduino_*.h (which would be better named something like
"atmega_*.h).
This meant to be a firmware-provided retract feature but was
never really supported by G-code generators. Without their support
(by issueing M101/M103), it's pretty hard to detect extrusion
pauses, so this feature simply has no future.
As this was on by default, it saves over 200 bytes binary size
in a default configuration.
The requirement was simply neither obvious nor intuitive. Drawback
is, the indices of temperature sensors can now differ from these
of the heaters. That's easier to recognize for newbies, though.
The atmega32u4 timer 4 registers differ from other AVRs, requiring
changes in heater.c and mendel.c The teensy/atmega32u4 uses LUFA USB,
but does not have 'usb' in the name, requiring changes in the
makefile PID values read from a blank EEPROM are set to default
rather than using zeros.
Markus Hitter
David Forrest