Skip to content

Double I2C read in one transaction skips a clock pulse (#5528) #6654

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 9 commits into from
Oct 27, 2019
Merged

Double I2C read in one transaction skips a clock pulse (#5528) #6654

Changes from all commits
Commits
Show all changes
9 commits
Select commit Hold shift + click to select a range
63518a0
Double I2C read in one transaction skips a clock pulse (#5528)
TD-er Oct 19, 2019
8357a8c
Merge branch 'master' into bugfix/issue5528_I2C_3rd
earlephilhower Oct 19, 2019
aac1295
[I2C] Restore clock stretch functionality during transfer
TD-er Oct 26, 2019
42515d7
Merge remote-tracking branch 'origin/bugfix/issue5528_I2C_3rd' into b…
TD-er Oct 26, 2019
3c2d332
Merge branch 'master' into bugfix/issue5528_I2C_3rd
earlephilhower Oct 26, 2019
254810f
Merge branch 'master' into bugfix/issue5528_I2C_3rd
earlephilhower Oct 26, 2019
702361c
[I2C] Move duplicated clock stretch call to twi_scl_valley function
TD-er Oct 26, 2019
fa9461f
Merge remote-tracking branch 'origin/bugfix/issue5528_I2C_3rd' into b…
TD-er Oct 26, 2019
5a3faec
Merge branch 'master' into bugfix/issue5528_I2C_3rd
earlephilhower Oct 26, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
32 changes: 24 additions & 8 deletions cores/esp8266/core_esp8266_si2c.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -128,6 +128,8 @@ class Twi
}
}

// Generate a clock "valley" (at the end of a segment, just before a repeated start)
void twi_scl_valley(void);

public:
void setClock(unsigned int freq);
Expand Down Expand Up @@ -386,13 +388,16 @@ unsigned char Twi::writeTo(unsigned char address, unsigned char * buf, unsigned
{
write_stop();
}
else
{
twi_scl_valley();
// TD-er: Also busywait(twi_dcount) here?
// busywait(twi_dcount);
}
i = 0;
while (!SDA_READ() && (i++) < 10)
{
SCL_LOW();
busywait(twi_dcount);
SCL_HIGH();
WAIT_CLOCK_STRETCH();
twi_scl_valley();
busywait(twi_dcount);
}
return 0;
Expand Down Expand Up @@ -422,13 +427,16 @@ unsigned char Twi::readFrom(unsigned char address, unsigned char* buf, unsigned
{
write_stop();
}
else
{
twi_scl_valley();
// TD-er: Also busywait(twi_dcount) here?
// busywait(twi_dcount);
}
i = 0;
while (!SDA_READ() && (i++) < 10)
{
SCL_LOW();
busywait(twi_dcount);
SCL_HIGH();
WAIT_CLOCK_STRETCH();
twi_scl_valley();
busywait(twi_dcount);
}
return 0;
Expand Down Expand Up @@ -649,6 +657,14 @@ void ICACHE_RAM_ATTR Twi::onTwipEvent(uint8_t status)
}
}

void Twi::twi_scl_valley(void)
{
SCL_LOW();
busywait(twi_dcount);
SCL_HIGH();
WAIT_CLOCK_STRETCH();
}

void ICACHE_RAM_ATTR Twi::onTimer(void *unused)
{
(void)unused;
Expand Down