Remove i2c write command when reading columns on Ergodox EZ #8092
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
drashna
approved these changes
Feb 5, 2020
zvecr
reviewed
Feb 5, 2020
|
I agree that we'd want the comment, but also I think this is sort of brilliant and I'm impressed. |
zvecr
approved these changes
Feb 5, 2020
Shinichi-Ohki
added a commit
to Shinichi-Ohki/qmk_firmware
that referenced
this pull request
Feb 8, 2020
* 'master' of https://github.com/qmk/qmk_firmware: (24 commits) CI: Add workflow for CLI testing (qmk#7357) Add Prime_L V2 and Prime_EXL Plus (qmk#8111) [Keyboard] adding keyboard: neuron (qmk#7980) [Keyboard] adding keyboard: pain27 (qmk#7977) [Keyboard] adding keyboard: sl40 (qmk#7978) [Keyboard] adding keyboard: houndstooth (qmk#7981) [Keyboard] adding keyboard: kodachi50 (qmk#7976) [Keyboard] adding keyboard: gothic70 (qmk#7982) [Keyboard] adding keyboard: gothic50 (qmk#7983) [Keyboard] YMDK NP21: matrix and keymap refactor (qmk#8112) [Keymap] Added keymap for keebio/nyquist (qmk#8108) [Keyboard] Port SPLIT_USB_DETECT to lily58 (qmk#8107) [Keymap] Phoebe/Maxr1998 keymap: enable space cadet with curly braces (qmk#8096) [Keymap] add lily58 yshrsmz keymap (qmk#8095) [Keyboard] Remove i2c write command when reading columns on Ergodox EZ (qmk#8092) [Keyboard] Misc tidyups for Chidori (qmk#8091) [Keymap] Add users/alfrdmalr and switch to layouts (qmk#8030) XD84: Configurator bugfix for ISO layout (qmk#8117) ZJ68: complete Configurator layout support (qmk#8116) Add QMK Compile Context Sensitivity (qmk#6884) ...
drashna
pushed a commit
to zsa/qmk_firmware
that referenced
this pull request
Feb 15, 2020
qmk#8092) * Remove i2c write command when reading cols on Ergodox EZ * Comment on mcp23018 address state during read_cols
fdidron
pushed a commit
to zsa/qmk_firmware
that referenced
this pull request
Feb 15, 2020
qmk#8092) * Remove i2c write command when reading cols on Ergodox EZ * Comment on mcp23018 address state during read_cols
HokieGeek
pushed a commit
to HokieGeek/qmk_firmware
that referenced
this pull request
Feb 21, 2020
qmk#8092) * Remove i2c write command when reading cols on Ergodox EZ * Comment on mcp23018 address state during read_cols
fdidron
pushed a commit
to zsa/qmk_firmware
that referenced
this pull request
Feb 26, 2020
qmk#8092) * Remove i2c write command when reading cols on Ergodox EZ * Comment on mcp23018 address state during read_cols
c0psrul3
pushed a commit
to c0psrul3/qmk_firmware
that referenced
this pull request
Mar 23, 2020
qmk#8092) * Remove i2c write command when reading cols on Ergodox EZ * Comment on mcp23018 address state during read_cols
kylekuj
pushed a commit
to kylekuj/qmk_firmware
that referenced
this pull request
Apr 21, 2020
qmk#8092) * Remove i2c write command when reading cols on Ergodox EZ * Comment on mcp23018 address state during read_cols
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.
Description
Since the IO expander is sequential mode (IOCON.SEQOP = 0), the address pointer is set to GPIOB (columns to be read) register after the row selection write operation on GPIOA so this write-restart to set address to GPIOB is unnecessary.
I also looked into special byte mode (IOCON.SEQOP = 1, IOCON.BANK = 0) that should cause the address pointer to toggle between GPIOA and GPIOB, but it doesn't look like you should write without sending the register address from the MCP23018 datasheet Figure 1-1 so there were no other savings.
This improves scan rate from 590 to 790.
@seebs
Types of Changes
Checklist