some people are starting to ask why homing is so slow. this is the old standard hard-coded value.

Z_DUAL_ENDSTOPS is a feature to enable the use of 2 endstops for both Z
steppers - Let's call them Z stepper and Z2 stepper.
That way the machine is capable to align the bed during home, since both
Z steppers are homed.
There is also an implementation of M666 (software endstops adjustment)
to this feature.
After Z homing, this adjustment is applied to just one of the steppers
in order to align the bed.
One just need to home the Z axis and measure the distance difference
between both Z axis and apply the math: Z adjust = Z - Z2.
If the Z stepper axis is closer to the bed, the measure Z > Z2 (yes, it
is.. think about it) and the Z adjust would be positive.
Play a little bit with small adjustments (0.5mm) and check the
behaviour.
The M119 (endstops report) will start reporting the Z2 Endstop as well.

- `Conditionals.h` is included twice, setting LCD values the first time

- Add `Conditionals.h` with calculated configuration values
- Add `SanityCheck.h` with checks for configuration errors
- Remove equivalent code from all configurations
- Move error checks from some sources to `SanityCheck.h` also
- Fix initialization of count_direction in stepper.cpp

- Also update base configs

- Both TMC, L6470 and pin-driven drivers work.
- All can be mixed and matched as needed.

This define is not used.

Small changes (and formatting to confuse the diff’er) which first
allows DOGLCD and LCD_PROGRESS_BAR to be enabled in tandem, then a
#warning (rather than error) that the extra progress bar / message
options don’t apply to graphical displays at this time. This leaves
open perhaps combining the progress bar and message area in some future
(or forked custom) graphical LCD display arrangement (at which time the
relevant variables may be moved into ultralcd.cpp with externs in
ultralcd.h). I also added a conditional error that the progress bar and
the filament display may not work well together.

- Fixed issue when BAL area probing is shorter than it should be for
grid probing
- Warning when BAL activated with Delta Kinematics
- Fix XY_TRAVEL_SPEED when homing Z axis

For legacy boards it’s better if this option is disabled.

First iteration of alphabetical sorting for SD cards, both
slow+efficient and fast+rammy. Option for folders to sort first, last,
or not at all.

For legacy boards it’s better if this option is disabled.

Tosh stepper drivers need to be driven slower, so the stepper code
was interleaved to separate the pin HIGH from the pin LOW. This adds
enough instructions to make it work, without needing nops.

# The first commit's message is:
SD Card Alpha Sorting

First iteration of alphabetical sorting for SD cards, both
slow+efficient and fast+rammy. Option for folders to sort first, last,
or not at all.

# This is the 2nd commit message:

Expand on More RAM concept, address minor bugs

# This is the 3rd commit message:

Improvements, more SORT_USES_MORE_RAM

With this option, always keeps the dir in RAM, doubling as a cache for
getfilename. A board with only 8K of SRAM is cutting it very close.

# This is the 4th commit message:

Completed SORT_USES_MORE_RAM implementation

For the MORE_RAM option we need to buffer both the short and long
names, even though long names are sometimes redundant. Worst case, all
the names are max length. We can save some RAM by not storing these. We
could save more RAM by only storing the visible part of the long name.

First iteration of alphabetical sorting for SD cards, both
slow+efficient and fast+rammy. Option for folders to sort first, last,
or not at all.

First iteration of alphabetical sorting for SD cards, both
slow+efficient and fast+rammy. Option for folders to sort first, last,
or not at all.

FW retraction is extended onto swap retraction invoked by 'G10 S1'.
Bookkeeping of the retract state of all extruders allows for having one
extruder fw standard retracted while another extruder is swap retracted.
An LCD menu item for the swap retract and recover length was added.

Corrected error in AUTOTEMP instructions

Firmware retraction now stores the retract and recover speeds in mm/s
instead of mm/min. This makes it match the units of the maximum
feedrate, and fixes problems with modifying the value via LCD control
panel. From gcode, the values are still taken in mm/min to match the
units of G1 and similar, and they are converted to mm/s before they are
stored.

I also lowered the default retract feedrate to make it less likely to
cause problems for geared extruders when the user hasn’t bothered to
set a reasonable maximum feedrate, though users should be setting both
of these values to suit their hardware.

Signed-off-by: Matthew Schick <matthew.schick@gmail.com>

Added so M240 can be used to trigger CHDK instead of sending an IR signal, see more about CHDK here http://captain-slow.dk/2014/03/09/3d-printing-timelapses/

Increase Z_HOME_RETRACT_MM to 2mm default to avoid end stop not switching during retract.

Add digipot i2c control for MCP4451
Allow M907 to set i2c digipot currents in amps
Fix Makefile to allow Azteeg motherboards
Fix Makefile to allow Wire libraries only
Add beeper pin for Azteeg X3 Pro

if you try to enable Z_DUAL_STEPPER_DRIVERS the error "You cannot have dual drivers for both Y and Z" shows even if you don't have defined Y_DUAL_STEPPER_DRIVERS and don't let you compile the firmware

to solve this problem i change this line:

#ifdef Z_DUAL_STEPPER_DRIVERS && Y_DUAL_STEPPER_DRIVERS

to:

#if defined (Z_DUAL_STEPPER_DRIVERS) && defined (Y_DUAL_STEPPER_DRIVERS)

now the error only show if you define both Z_DUAL_STEPPER_DRIVERS and Y_DUAL_STEPPER_DRIVERS

This allows a hot end with two heaters and a FET for each heater. This is useful if the FET is not capable of heating two heaters.

Included support for BT dongle on AT90USB boards.
Added LCD Shift Register LCD control
Included support for RepRap Clone Wars project board (SAV MKI).