If Marlin is inside the temperature ISR, the stepper ISR is enabled. If
a stepper event is now happening Marlin will proceed with the stepper
ISR. Now, at the end of the stepper ISR, the temperatre ISR gets enabled
again. While Marlin proceed the rest of the temperature ISR, it's now
vulnerable to a second ISR call.
To guarantee that the 5mS pulse from a BLTouch is recognized you need to
have the endstops.update() routine run twice in that 5mS period.
At 200 steps per mm, my system has problems below a feedrate of 120 mm
per minute.
Two things were done to guarantee the two updates within 5mS:
1) In interrupt mode, a check was added to the temperature ISR. If the
endstop interrupt flag/counter is active then it'll kick off the endstop
update routine every 1mS until the flag/counter is zero. This
flag/counter is decremented by the temperature ISR AND by the stepper
ISR.
2) In poling mode, code was added to the stepper ISR that will make sure
the ISR runs about every 1.5mS. The "extra" ISR runs only check the
endstops. This was done by grabbing the intended ISR delay and, if it's
over 2.0mS, splitting the intended delay into multiple smaller delays.
The first delay can be up to 2.0mS, the next ones 1.5mS (as needed) and
the last no less than 0.5mS.
=========================================
BLTouch error state recovery
If BLTouch already active when deploying the probe then try to reset it
& clear the probe.
If that doesn't fix it then declare an error.
Also added BLTouch init routine to startup section
Replace all fastDigitalRead/Write() with READ/WRITE()
Define SCK_PIN, MISO_PIN, MOSI_PIN in pins.h if not already defined in the pins_*.h files.
Remove these conditional pin definitions from the pin-files. They are now always defined.
Define separate sets of SPI-pins for AT90USB with and without Teensy support in fastio.h.
Likely this was the main reason for all that confusion about the AT90USB-SPI pins.
Add an emergency-command parser to MarlinSerial's RX interrupt.
The parser tries to find and execute M108,M112,M410 before the commands disappear in the RX-buffer.
To avoid false positives for M117, comments and commands followed by filenames (M23, M28, M30, M32, M33) are filtered.
This enables Marlin to receive and react on the Emergency command at all times - regardless of whether the buffers are full or not. It remains to convince hosts to send the commands. To inform the hosts about the new feature a new entry in the M115-report was made. "`EMERGENCY_CODES:M112,M108,M410;`".
The parser is fast. It only ever needs two switch decisions and one assignment of the new state for every character.
One problem remains. If the host has sent an incomplete line before sending an emergency command the emergency command could be omitted when the parser is in `state_IGNORE`.
In that case the host should send "\ncommand\n"
Also introduces M108 to break the waiting for the heaters in M109, M190 and M303.
Rename `cancel_heatup` to `wait_for_heatup` to better see the purpose.
When setting the bed temp via M140/M190 if the thermistor does not read an increase of WATCH_BED_TEMP_INCREASE degrees by WATCH_BED_TEMP_PERIOD seconds then it will throw "Error:Heating failed, system stopped! Heater_ID: bed" and call the kill() function.
Conflicts:
Marlin/Configuration_adv.h