The Wio Terminal includes a RealTek RTL8720D as a companion to the main chip to provide WiFi and Bluetooth capabilities via eRPC over a UART connection. The WIO Terminal schematic labels some pins as the RXD/TXD for the UART, and that was captured in the board definition for CircuitPython. However, these pins may be used for logging in another mode, but they are not the main pins used to communicate with the RTL chip. The correct configuration is RX on PC24/pad 2 and TX on PB24/pad 0 of SERCOM 0. The comments on the pin definitions now reflect this situation, for anyone trying to get the WiFi/BLE to work on the Wio Terminal.
Previous pins definition stated that the UART1 RTS and CTS were not connected. They are connected and can currently be used via A1 and PWM0 respectively. To make things a little clearer, enabling the RTS1/CTS1.
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.
* Enable dcache for OCRAM where the VM heap lives.
* Add CIRCUITPY_SWO_TRACE for pushing program counters out over the
SWO pin via the ITM module in the CPU. Exempt some functions from
instrumentation to reduce traffic and allow inlining.
* Place more functions in ITCM to handle errors using code in RAM-only
and speed up CP.
* Use SET and CLEAR registers for digitalio. The SDK does read, mask
and write.
* Switch to 2MiB reserved for CircuitPython code. Up from 1MiB.
* Run USB interrupts during flash erase and write.
* Allow storage writes from CP if the USB drive is disabled.
* Get perf bench tests running on CircuitPython and increase timeouts
so it works when instrumentation is active.
It now handles deinit, never_reset and sharing tracking. PWM
now runs in the WAIT state as well during a time.sleep().
_reset_ok() was removed because it was called in one spot right
before deinit().
Some PWMOut were also switched to a bitmap for use instead of
reference count. That way init and deinit are idempotent.
Fixes#6589. Fixes#4841. Fixes#4541.