Check for 3.3V supply before raising IRQ and continuing boot process #72
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
jannic
commented
Jan 28, 2025
|
Nice catch, thanks! |
thejpster
reviewed
Jan 28, 2025
neotron-bmc-pico/src/main.rs
Outdated
| if ctx.shared.state_dc_power_enabled.lock(|r| *r) == DcPowerState::Starting { | ||
| let mon_3v3 = ctx.local.adc.read_abs_mv(ctx.local.pin_3v3_monitor); | ||
| defmt::trace!("3v3 reading: {}", mon_3v3); | ||
| if mon_3v3 < 1600 { |
There was a problem hiding this comment.
Why 1600mV? That seems quite low?
There was a problem hiding this comment.
There is a voltage divider before the ADC. 1600mV on the pin means 3.2V on the 3.3V rail.
So 1600mV may actually be too high. I didn't do an estimate of the tolerances.
There was a problem hiding this comment.
(If you agree with the general approach, I can work on the details, like adding some explanations, putting the "magic value" 1600 in a const etc.)
There was a problem hiding this comment.
Ahhhh. Yes, you can't exceed fairly tight limits on the ADC pin so I halved the input.
Yes the approach makes sense.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Signals:
1: 3.3V
2: 5V
4: IRQ0
Before:
With this fix:
