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.
7ea192af05