Add Bit transpose function to support piopixl8 #4219
Merged
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
.. this version can only handle exactly 8 bits "across". The restriction may be relaxed in a future revision.
tannewt
requested changes
Feb 18, 2021
|
Renamed to "bitops", improved documentation, made output required, made width= positional. |
tannewt
approved these changes
Feb 18, 2021
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Outdated suggestions cannot be applied.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.
We want to speed up writing neopixels by nearly 8x on RP2040 by placing multiple strands in parallel and driving them with PIO. This needs a very specific bit rearrangement calculation which is too slow to do in Python but can be done very efficiently in C.
Testing performed: with work-in-progress
adafruit_piopixl8library, drove 2 to 8 strands of 30 real LEDs each; also stress tested the library by driving 25600 imaginary LEDs at a rate of about 240,000 pixels/second (theoretical max: about 266,667 pixels/second)