STM32G0 SYSCLK can be sourced from PLLRCLK. Given that the HSI runs at
16 MHz and the HSE range is 4-48 MHz, the PLL is the only way to reach
64 MHz. This commit adds `ClockSrc::PLL`.
The PLL sources from either HSI16 or HSE, divides it by `m`, and locks
its VCO to multiple `n`. It then divides the VCO by `r`, `p`, and `q`
to produce up to three associated clock signals:
* PLLRCLK is one of the inputs on the SYSCLK mux. This is the main
reason the user will configure the PLL, so `r` is mandatory and
the output is enabled unconditionally.
* PLLPCLK is available as a clock source for the ADC and I2S
peripherals, so `p` is optional and the output is conditional.
* PLLQCLK exists only on STM32G0B0xx, and exists only to feed the
MCO and MCO2 peripherals, so `q` is optional and the output is
conditional.
When the user specifies `ClockSrc::PLL(PllConfig)`, `rcc::init()`
calls `PllConfig::init()` which initializes the PLL per [RM0454]. It
disables the PLL, waits for it to stop, enables the source
oscillator, configures the PLL, waits for it to lock, and then
enables the appropriate outputs. `rcc::init()` then switches the
clock source to PLLRCLK.
`rcc::init()` is now also resonsible for calculating and setting flash
wait states. SYSCLCK < 24 MHz is fine in the reset state, but 24-48 MHz
requires waiting 1 cycle and 48-64 MHz requires waiting 2 cycles. (This
was likely a blocker for anyone using HSE >= 24 MHz, with or without
the PLL.) Flash accesses are now automatically slowed down as needed
before changing the clock source, and sped up as permitted after
changing the clock source. The number of flash wait states also
determines if flash prefetching will be profitable, so that is now
handled automatically too.
[RM0454]: https://www.st.com/resource/en/reference_manual/rm0454-stm32g0x0-advanced-armbased-32bit-mcus-stmicroelectronics.pdf
783: Reimplement BufRead for BufferedUart r=Dirbaio a=chemicstry
The `AsyncBufRead` implementation for `BufferedUart` was removed in https://github.com/embassy-rs/embassy/pull/752, this PR reimplements it from `embedded-io`. This allows reading `BufferedUart` without copying slices.
Co-authored-by: chemicstry <chemicstry@gmail.com>
770: Add open-drain support for embassy-rp r=danbev a=danbev
This commit adds open-drain support for embassy-rp by adding a new type
named `embassy_rp::gpio::OutputOpenDrain`.
Co-authored-by: Daniel Bevenius <daniel.bevenius@gmail.com>
780: Add new lines between SIO methods r=Dirbaio a=danbev
The commit adds new lines between the SIO functions which at least for
me improves readability and is consistent with the other methods in the
trait.
Co-authored-by: Daniel Bevenius <daniel.bevenius@gmail.com>
776: Automatically set ADC clock prescaler on v2 ADC to respect max frequency r=Dirbaio a=matoushybl
Co-authored-by: Matous Hybl <hyblmatous@gmail.com>
777: usb-ncm: remove useless Cell. r=Dirbaio a=Dirbaio
This allows the CDC-NCM class struct to be Send, so you can run
it at a different priority than the main USB stack task.
bors r+
Co-authored-by: Dario Nieuwenhuis <dirbaio@dirbaio.net>
768: nrf/usb: fix control out transfers getting corrupted due to ep0rcvout sticking from earlier. r=Dirbaio a=Dirbaio
bors r+
Co-authored-by: Dario Nieuwenhuis <dirbaio@dirbaio.net>
756: Add async quadrature decoder for embassy-nrf r=Dirbaio a=kalkyl
Thsi PR adds an async interface to the QDEC peripheral to embassy-nrf, that can be used for rotary encoders for example.
Co-authored-by: Henrik Alsér <henrik@mindbite.se>
Co-authored-by: Henrik Alsér <henrik.alser@me.com>
Co-authored-by: Henrik Alsér <henrik.alser@me.com>
767: Stm32 fixes r=lulf a=jr-oss
Using embassy on STM32 Discovery board showed problems with
- USART with parity
- Clock settings (CFGR) when using PLL and prescaler
- Flash ACR settings
This PR attempts to fix these
Co-authored-by: Ralf <jr-oss@gmx.net>
PLL settings remained intact because these bits are not writable when PLL is enabled,
but prescaler settings were overwritten by selecting PLL as sysclk (CFGR.SW[1:0]).
765: Implement Output::is_set_low for embassy-rp r=Dirbaio a=danbev
This commit implements a suggestion for the method `is_set_low` which is
currently a `todo`, by reading last value written to `GPIO_OUT`.
Co-authored-by: Daniel Bevenius <daniel.bevenius@gmail.com>
