2398040_en-US

FETMX6ULL-C: Random CTP I2C communication errors when LCD and CTP are connected simultaneously, CTP

Hardware platform: FETMX6ULL-C core board.

Capacitive Touch Panel (CTP) GT911 works stably without any I2C errors when only the CTP is connected.

After connecting both LCD display and CTP at the same time, random I2C communication exceptions occur on CTP, which leads to touch function failure occasionally.

We suspect that electromagnetic interference introduced by the LCD circuit causes unstable I2C signal of the touch panel.

Related kernel dmesg logs are attached for analysis.

Our software environment: Linux 4.1.15 BSP.

CTP communicates via I2C bus. We have checked hardware wiring and power supply, but the issue still exists.

Looking forward to your technical suggestions.