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Has anyone ever gotten the I2C LCD display AND the Si5351 clock chip to operate on SDA2/SCL2?? Looking to get that running on a Teensy3.6 if possible.? Any help from the group would be very much appreciated.

Jim Sheldon, W0EB

Those pullups to 3.3v for SDA,SCL are already on the Raduino board so the Nano can talk to the si5351.
All that is needed is to remove the 5v pullups from your i2c display.
If it's an LCD display with backpack, see this post for more info:
? ? /g/BITX20/message/39966?

Jerry

I don't think the issue is the bus voltage.

The issue is getting the SDA2 and SCL2 pins to work instead of SDA1 and
SCL1.

The Wire library seems to only handle SDA and SCL, not any of the other
SDA/SCL combinations available on the Teensy.

tim ab0wr

On Thu, 31 May 2018 23:31:32 -0500
"AA9GG" <paul.aa9gg@...> wrote:

Haven't tried it, but remember that the si part is running at 3v and
the display is at 5v. Therfore you will need to use 4.7k resistors
to pull the SDA and SCL lines to 3v (NOT 5v). Make sure you remove
the pull-ups off of the lcd if they are present and just use the ones
in the si circuit.

There is a separate library for Teensy (i2c_t3) that comes as a built in library in the Teensy add-on for the IDE.
It is supposed to handle Wire1, Wire2, Wire3, and Wire4
#include <i2C_t3.h> instead of #include <Wire.h>

But apparently the LCD library may only be able to access Wire1

N5IB