OPT4001: Sensors forum I2C

haitao.zhang

Part Number: OPT4001

Tool/software:

When we were debugging the I2C data of the OPT4001, since our I2C was simulated by Flex io, in the test results, it was found that when reading the data of the OPT4001, the MCU occasionally failed to generate the Stop signal normally, which would drag down the SDA bus time by up to 100ms, causing bus data errors. Are there any special requirements for the I2C opt4001, such as the main unit needing to have the Stretch function, etc., or do you have any experience to share in this regard

26 days ago

0 Joseph Scherphorn 25 days ago

TI__Expert 4120 points

Hello Haitao,

Are you operating device in standard mode (up to 100 kHz), fast mode (up to 400 kHz), or high-speed mode (up to 2.6 MHz)?

0 haitao.zhang 25 days ago in reply to Joseph Scherphorn

Prodigy 20 points

Good morning ，Joseph

The I2C frequency we simulated using Flex IO is approximately 340KHz

0 Joseph Scherphorn 24 days ago in reply to haitao.zhang

TI__Expert 4120 points

Hello Haitao,

Could you provide configuration register settings please?

Could you please include a scope shot of the SCL and SDA waveforms.

Thank you,

Joseph Scherphorn

0 haitao.zhang 24 days ago in reply to Joseph Scherphorn

Prodigy 20 points

Joseph，This is our test waveforms ，can occur error of ACK,After can occur to pull down of SDA

0 haitao.zhang 24 days ago in reply to haitao.zhang

Prodigy 20 points

We changed the I2C channel to LPI2C(HW MODule) ,Test the I2C Trigger the Clock stretch ， no fault ，I want konw if the OPT4001 requiret Master have the Stretch When normal work？

0 haitao.zhang 23 days ago in reply to haitao.zhang

Prodigy 20 points

Hello Joseph，We checked Flex IO I2C don't support NACK,For this kind of thing, can we only replace it with LPI2C(hardware module, MCU comes with I2C)？，There are still other methods？