Hello Somnuk,

The Hantronix module uses the Hitachi HD66712 driver.

I do hope that you downloaded the data sheet for this driver. This is a 24Cx1L or 12Cx2L display driver.

But the Hantronix module is 20C type.

And since you say that you have a repetition from 13th character, maybe you have to change the line address after the 12th chracter - I am just guessing from the data sheet information.

Raghu