Tidied up axis homing tracking.
When checking endstops, wait for move to complete before accepting
further moves, otherwise subsequent moves use the wrong coordinates.
Temperatures and Z probes are now monitored continuously using a tick
interrupt to kick off ADC conversions. ADC is now run in 12-bit mode.
Thermistor readings are passed through averaging filters. Thermistors
are monitored for overheat conditions and bad readings in the tick ISR
and the appropriate heater is turned off (useful because the main loop
sometimes gets suspended while trying to do USB communication).
Use watchdog timer to monitor the tick interrupt - needs patch to
Arduino Due core library. Add facility to test watchdog timer (M111
S1001). Added an error status word to record that errors have occurred
(e.g. over-temperature).
M111 command changes so that S0 turns debug off, S1 turns debug on, S2
reports free memory - also now reports the type of the last restart and
the error status word. Fixed problem whereby M111 debug reports were not
sent to the web interface.
Implemented M999 command, which resets the Duet.
Removed an unused variable.
Changed some more "char*" to "const char*".
Changed extruder PID parameters and added more explanation for them.
Fixed M106 command so that the cooling fan is controllably by PWM and
works the right way round (0 = off, 1 = on). Also added optional P
parameter to specify the value that corresponds to maximum PWM.
1. Z-probing is now done in two stages: a fast stage at the configured
home feed rate until within 10% of the target value, then a slow stage
at 20% of that feed rate.
2. Provisional support for ultrasonic Z-probe.
3. Added calibration temperature and height temperature coefficient to Z
probe parameters.
4. Z-probe parameters and Z-probe type are now saved to flash memory so
that they survive power-off and reset cycles. Separate parameters are
retained for IR and ultrasonic probes in case both are fitted.
5. Fixed issue with doing slow Z-moves immediately after Z-homing or
probing.
Remember whether each axis has been homed. Don't allow z-homing or G31
procedure unless X and Y have been homed. If axes have been homed, limit
travel to size of bed.
Increase incoming web gcode buffer size to 1200 chars to allow more
gcodes to be sent in each message
Include free buffer size in poll response
Include response sequence number in poll response
Implement M30 (delete file) via USB interface
Support M503 and M111 commands via web interface
Added new fields "zprobe" and "resp" to webserver poll response
Immutable string parameters are passed as const char* not char*
Increase max number of files displayed to 42
Range-check heater parameters in incoming commands to avoid buffer
overflow if heater number is out of range
Fixed printing over USB and via HTTP so that it uses the same lookahead
mechanism as for printing from SD provided the data arrives fast enough.
Added an incoming buffer for data arriving from USB. NOTE: Pronterface
needs to be patched to send the data fast enough for this to work well.
Also changed signatures of some member functions to be const-correct
1. Z home now moves home, rather than just setting the coordinate.
2. Wait for temps implemented.
Also the JSON requests for the g code filelist has been temporarily commented
out in reprap.htm. It was causing the firmware to hang sometimes. To be investigated.
Machine now prints nicely...
track up the low-precision slope of the IR probe before measuring down
the high-precision slope near 0 mm. But this means that the probe has to
be set only a fraction of a mm higher than the nozzle itself. Also (at
the moment for safety) the code thinks Z = 0 occurs when it is actually
0.2mm. This is easy to fix when the rest is reliable.
