SAA1064 and UNO dont talk [ SOLVED #4]

I had a problem and was searching for solutions. This exactly is my issue :

SAA1064 issue

As per the OP in that post, he was able to get the code working once he replaced the UNO with a bare board 328P.

But that does not point to any issue … just that he got lucky maybe. Any tips on how this can happen … ? I am actually planning to check with a Mega 2650 and will post back after that.

He changed his code but claimed he had not! Just look at his loop()

Mark

holmes4:
He changed his code but claimed he had not! Just look at his loop()

Mark

I don't know about that … but the code was " looking" OK with no noticeable bugs. Or is there some ?

OK it was all about the resistors on the SCL and SDA lines. And I am now able to get it going with a ESP32 module also as per the attached figure.

Now the next problem is : How to get it working for a display module that has a Vf at about 8V ? I tried to hook it up like shown in the schematic attached but it does not work … the display appears dead. But the moment I hook up the Display Power back to 5V its working fine .

How to get the SAA1064 work with high voltage display modules ?
SAA1064_Circuit_HighVoltage.jpg

As they say putting down any problem on paper helps solve it.
So in my case too … one look at the sketch showed that SCL and SDA lines are floating at the Display driver end. So shifted the two 2.2K resistors from the 3.3V to the 5V side and the setup is working great … I can now use displays which have a Vf of upto 15V which the SAA1064 is capable of handling. Those will be real jumbo displays !!