⚠️ RPI prevents the ER-301 from booting up normally, they need to start simultaneously

Question

⚠️ RPI prevents the ER-301 from booting up normally, they need to start simultaneously

Closed this issue 4 years ago · 2 comments

⚠️ Connecting the Raspberry PI directly to the ER-301 module or even to the same i2c bus is a source of problems. If the two devices are not started simultaneously, or if the ER-301 is powered on after the RPI, the Raspberry Pi will prevent the ER-301 from starting normally.

(The ER-301 uses the bus for UART during its startup, it pulls the line down => Conflict with the RPI i2c hardware gpio)

To overcome this problem, it is prefereable to create an external circuit including two 4.7k pull-up resistors and use another set of GPIO on the Raspberry for i2c (aka. "Software i2c overlay") rather than the "hardware i2c gpio".

Answer 1 · 2020-07-07T19:09:20.000Z

An hardware solution is currently being created.

Answer 2 · 2020-07-26T17:11:09.000Z

Considered fixed with Hans hat and a software i2c bus.
No work will be done for the hardware i2c bus.