There are apparently two RTC interfaces in the mimxrt10xx dev
kit. The low power interface access the battery backed up hardware.
I've tested this on the Teensy41 and it seems to
fix issue #4574
- define CIRCUITPY_BUILD_EXTENSIONS to predefined values
- set CIRCUITPY_BUILD_EXTENSIONS in port and board config
- reuse the support matrix "get_settings_from_makefile" to get it
- move the existing port and board specific values
- remove the C3 specific board values because it's not the default
- update build_release_files.py to use get_settings_from_makefile
Everything should be using the keypad module instead.
Note: there are several boards that still had gamepadshift enabled. I
did not contact their authors to make sure they already switched to
keypad in their code and documentation. We should probably wait with
merging this for their go ahead.
Changed a few things in the link step that satisfies the teensy
loader apps, both the teensy.exe as well as the teensy_loader_cli
such that when you program the board again it should retain the
file sytem that is stored in the upper area of the Flash
there return of a read operation that times out with no data received
is inconsistent:
```
Adafruit CircuitPython 7.3.0-beta.1-31-g73f6b4867-dirty on 2022-04-30; Adafruit Feather RP2040 with rp2040
>>>
>>> import board, busio
>>> print(board.UART().read(5))
None
Adafruit CircuitPython 6.3.0 on 2021-06-01; FeatherS2 with ESP32S2
>>> import board,busio
>>> print(board.UART().read(5))
None
Adafruit CircuitPython 7.3.0-beta.1 on 2022-04-07; Adafruit Feather STM32F405 Express with STM32F405RG
>>> import board, busio
>>> print(board.UART().read(5))
None
Adafruit CircuitPython 7.3.0-beta.1-31-g73f6b4867-dirty on 2022-04-28; Teensy 4.1 with IMXRT1062DVJ6A
>>> import board, busio
>>> print(board.UART().read(5))
b''
```
Since I have a PR on this file anyway, I thought I would put in the change to make it consistent
with the other 3 board types I tried. Can not say about any of the others.
The existing code was setup that allowed you to specify an RTS
pin to be used as an RS485 direction pin, however there are no
RTS pins that are exposed on any of the Teensy 4.x boards.
Instead Arduino code base allowed you to specify any GPIO pin to
work instead. So I added the code in to facilitate this.
In addition the alternative code to wrap your own GPIO pin set high and low
around call(s) to uart.write() will not currently work, unless maybe you
fudge it and add your own delays as the write will return after the last
byte was pushed onto the UART’s hardware FIFO queue and as such if you
then immediately set the IO pin low, it will corrupt your output stream.
The code I added detects that you are setup to use the RS485 pin and
before it returns will wait for the UART’s Transfer complete status flag
to be set.
There were two main issues with the PWM support.
The first is they would fail to work properly if the board goes
into low power mode, when you do things like: time.sleep(0.25)
Can make partially work with this by turning on the proper flags
in each of the FlexPWMTimer Timers/sub-timers, but this did not
appear to work if for example you have both A and B channels
enabled.
Second main problem is that the code did not work with the X
channel of each timer/sub-timer. It looks like someone had
earlier started support for this, But was not sufficient.
Needed to bypass the SDK code and get it closer to the PJRC code.
That is we set the PWM_CTRL_FULL_MASK, which then uses base->SM[submodule].VAL1 to control
when the timer is reset, so it sets up your cycle/frequency. But then this implies that X channel
which uses 0, 1 has to be handled specially. So for the different channels:
A - Uses VAL2 to turn on (0) and VAL3=duty to turn off
B - Uses VAL4 to turn on (0) and VAL5 to turn off
X - As mentioned above VAL1 turns off, but its set to the timing for freqency. so
VAL0 turns on, so we set it to VAL1 - duty
Renamed the board both name of directory within boards, but also the
name reported board name: board_id -- sparkfun_teensy_micromod
Adafruit CircuitPython 7.3.0-beta.0-10-g2a3eb49da-dirty on 2022-04-10; SparkFun Teensy MicroMod Processor with IMXRT1062DVL6A
While testing out this and the new MicroMod Teensy port, @mjs513
and myself found it desirable to have logical pin names for the
different Serial UART objects. It is a lot easier and clearer
to use and maintain to do something
like: uart4 = busio.UART(board.TX4, board.RX4)
than have to go look up the pin numbers for each board.
