During evaluation of the display of the LCD using an I2C interface I discovered the following issues
-
If you try to send more than 32 data bytes following the address, none of the characters are displayed. The display locks up and can only be brought back by powering down and up.
-
If you send multiple packets i.e. address, data, stop, there must be a significant delay of the order of a few ms between packets else characters could somrtimes be skipped.
These issues lead me to the conclusion that the product is not I2C compliant as I2C spec does not mention these requirements.
Would like a confirmation from from the developers that these observations are correct or if something is wrong with my eval.
Thanks.
It certainly works over i2c for me for normal operation
My post was about specific circumstances where it does not work. I have verified with multiple master devices (Arduino and Corelis) the following limitations
-
You cannot send more than 32 characters between start and stop signals. It will freeze.
-
There needs to be at least 500us of delay per character else characters can be skipped.
Of course, you are verifying operation with Arduino, you cannot send more than 32 characters anyway. So you cannot observe the first bug. But You can definitely observe the second. Please try to send consecutive strings with no delay and see what happens.
Hopefully, you can document these limitations in the product spec so users can benefit.