This adds a check to make sure that SDA and SCL are in a sane condition
before starting any I2C operation. If they are not it tries to rectify it,
and then returns an error code if unable to do so.
In my testing, the feather bluefruit can do 12 voices at 48kHz!
This is a simple case (no LFOs, no ring modulation) so other situations might
require a lower sample rate, fewer voices, or both.
The sound is a little artifacty & low-fi but I think that's down to the speaker
& use of PWM instead of I2S.
In #7497 port_background_task was renamed to port_background_tick
but the actual call site wasn't changed. This meant that it was
no longer called!
Rename more functions from task to tick to make it clearer which is
which.
Helps prevent the filesystem from getting formatted by mistake, among other
things. For example, on a Pico board, entering Ctrl+D and Ctrl+C fast many
times will eventually wipe the filesystem (without warning or notice).
Further rationale: Ctrl+C is used a lot by automation scripts (eg mpremote)
and UI's (eg Mu, Thonny) to get the board into a known state. If the board
is not responding for a short time then it's not possible to know if it's
just a slow start up (eg in _boot.py), or an infinite loop in the main
application. The former should not be interrupted, but the latter should.
The only way to distinguish these two cases would be to wait "long enough",
and if there's nothing on the serial after "long enough" then assume it's
running the application and Ctrl+C should break out of it. But defining
"long enough" is impossible for all the different boards and their possible
behaviour. The solution in this commit is to make it so that frozen
start-up code cannot be interrupted by Ctrl+C. That code then effectively
acts like normal C start-up code, which also cannot be interrupted.
Note: on the stm32 port this was never seen as an issue because all
start-up code is in C. But now other ports start to put more things in
_boot.py and so this problem crops up.
Signed-off-by: David Grayson <davidegrayson@gmail.com>
Changes in this commit:
- Move the pwm_seq array to the p_config data structure. That prevents
potential resource collisions between PWM devices.
- Rename the keyword argument 'id' to 'device'. That's consistent with the
SAMD port as the other port allowing to specify it.
This is a best-effort implementation of write polling. It's difficult to
do correctly because if there are multiple output streams (eg UART and USB
CDC) then some may not be writeable while others are. A full solution
should also have a return value from mp_hal_stdout_tx_strn(), returning the
number of bytes written to the stream(s). That's also hard to define.
The renesas-ra and stm32 ports already implement a similar best-effort
mechanism for write polling.
Fixes issue #11026.
Signed-off-by: Damien George <damien@micropython.org>
Previously, setting MICROPY_HW_ENABLE_USBDEV to 0 caused build errors. The
change affects the nrf and samd ports as well, so MICROPY_HW_ENABLE_USBDEV
had to be explicitly enabled there.
The configuration options MICROPY_HW_ENABLE_USBDEV and
MICROPY_HW_ENABLE_UART_REPL are independent, and can be enabled or disabled
by a board.
Signed-off-by: Damien George <damien@micropython.org>
Changes in this commit:
- Add the timeout and timeout_char keyword options.
- Make uart.read() non-blocking.
- Add uart.any().
- Add ioctl MP_STREAM_POLL handling.
- Change uart.write() into non-busy waiting. uart.write() still waits until
all data has been sent, but calls MICROPY_EVENT_POLL_HOOK while waiting.
uart.write() uses DMA for transfer. One option would be to add a small
local buffer, such that transfers up to the size of the buffer could be
done without waiting.
- As a side effect to the change of uart.write(), uart.txdone() and ioctl
flush now report/wait correctly for the end of transmission.
- Change machine_hard_uart_buf_t in machine_hard_uart_obj_t to an instance
of that struct, rather than a pointer to one.
These have the same frequency, but can have different duty cycle and
polarity.
pwm.deinit() stops all channels of a module, but does not release the
module. pwm.init() without arguments restarts all outputs.
