Re: DS1307 on rpi4B

> On 8 Dec 2024, at 14:42, 風來散人 <furaisanjin@gmail.com> wrote:
> I'm using this module (https://www.electronicwings.com/sensors-modules/real-time-clock-rtc-ds1307-module) and there are R2 and R3 for pull-up on the module. The registers are connected to 5V. This probably harms RPI4B because the voltage is 3.3V at RPI4B side. So I removed R2 and R3. That's why internal pull-up is required.

Ah that is unfortunate.

There is 3.3V on the 40 pin RPi header you could connect to R2/R3 (and cut the connection to 5V obviously).

--
Daniel O'Connor
"The nice thing about standards is that there
are so many of them to choose from."
-- Andrew Tanenbaum