/challenges-projects/design-challenges/experimenting-with-current-sense-amplifier/b/challenge-blog/posts/blog-3-mikroe-board-assembly-and-configurationThree blog posts in one day, what gives? We are currently in the grips of a snow storm that has closed roads and businesses. I have the time so why not blog with it. This post is designed to provide some details around physically assembling the two Men-USTelligent Community 12https://community.element14.com/challenges-projects/design-challenges/experimenting-with-current-sense-amplifier/b/challenge-blog/posts/blog-3-mikroe-board-assembly-and-configurationWed, 13 Apr 2022 21:40:57 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:4e2b7764-9874-478f-9fd1-518d00ed9187misaz1<p>Strange behaviour on I2C bus and slow response from&nbsp;<span>i2ctools </span> is caused by missing pullup resistors. Raspberry Pi has no onboard I2C pullups, so when you disconnected click board, bus became unrealible. Without resistors bus is not pulled high and has no determinisitic voltage until is driven by I2C controller which makes deterministic logical 0 on it. After driver release it, ti became unreliable again (it can stuck at zero or due to external induction can goes to up or down randomly). In this case I2C controller detect random (often invalid) operations on bus and randomly stucks in deadlocks which cause slowing i2ctool utilities. This is also cause of detecting random non-existing devices and so on.</p><img src="https://community.element14.com/aggbug?PostID=23394&AppID=364&AppType=Weblog&ContentType=0" width="1" height="1">