01:40 <broderick[m]> I'm looking to write a driver for a peripheral that would need a I/O pin that can switch between an input and output. The IoPin trait looks to have been dropped after e-h 0.2.7; what is the suggested way to handle this generically with the 1.0.0 prereleases?

01:51 <adamgreig[m]> See https://github.com/rust-embedded/embedded-hal/issues/397 for the discussion about it

07:39 <stensonb[m]> Silly, basic electronic question... I'm looking to read an analog knob potentiometer (via ADC, I think)...why would I choose 10k over 100k, or 1M ohm here....the circuit with the pot has no other load...and would be in series from vcc to the pin. If they all have the same physical travel, wouldn't they all scale the voltage identically?

07:45 <marmrt[m]> Your ADC will have some input impedance that might skew the measurement somewhat at very high resistances.

07:45 <marmrt[m]> Is it an application where saving a milliamp matters?

07:49 <barnabyw[m]> not sure what you mean by “in series from vcc to the pin”, usually you’d have the pot set up as a voltage divider with the wiper connected to the ADC pin for that use-case. So the whole resistance of the pot is connected between +va and 0v, and sees a constant current flow of +va/r

07:50 <barnabyw[m]> so with a +va of 3.3v and a 10k pot, there’s a constant 0.3mA current flowing through the pot, which you’re unlikely to notice unless you require extremely low power consumption

07:51 <stensonb[m]> No real need to save milliamps...yeah, I was trying to explain I'll have nothing else with the pot...just +va, 0v, and the divider output.

07:52 <stensonb[m]> Ah...so I have to make sure my chip can register voltage with such low current (if using 10k pot)

07:54 <barnabyw[m]> I don’t know of any general-purpose ADC which would have trouble with a 10k or 100k pot, typically they have an extremely high input impedance and can be understood to not consume any current (unless you’re worried about picoamps)

07:55 <stensonb[m]> Would the chip spec sheet have this detail for their ADC support (minimum current requirements)?

08:04 <marmrt[m]> Yeah, you should have Input Impedance or Input Current listed in an Electrical Characteristics chapter somewhere

11:31 <LiamKinne[m]> Hey all, does anyone know of a no-std compatible toml parser?

14:49 <Ecco> I have a questionr regarding Embassy, and more specifically it's HAL

14:49 <Ecco> In this sample code (https://github.com/embassy-rs/embassy/blob/main/examples/stm32wba/src/bin/blinky.rs), we configure PB4 as an output pin

14:50 <Ecco> Question-> How does it know to enable the appropriate bit in the RCC register?

14:50 <Ecco> Second question -> What if I temporarily want to gate clocks on GPIOs and manually change the RCC register?

16:07 <Ecco> Third question: does Embassy support the radio on STM32WBA?

17:33 <juliand[m]> <Ecco> "Question-> How does it know to..." <- Afaik they are enabled by default: see https://github.com/embassy-rs/embassy/blob/ce4dd67f3b4fb7d622a3d77b8a0a520dddd6fecf/embassy-stm32/src/lib.rs#L209 and https://github.com/embassy-rs/embassy/blob/ce4dd67f3b4fb7d622a3d77b8a0a520dddd6fecf/embassy-stm32/src/gpio.rs#L761

17:33 <juliand[m]> Also, there is another matrix chat for embassy, you might get more help there: https://matrix.to/#/#embassy-rs:matrix.org

17:33 <juliand[m]> Not sure if/how you could call the disable function, never tried that. But you can usually go the "manual" way through the PAC (https://docs.embassy.dev/stm32-metapac/git/stm32h743zi/rcc/struct.Rcc.html) if anything is not implemented in the HAL, yet.