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2.8" TFT Touch Shield Cap two I2C interfaces
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2.8" TFT Touch Shield Cap two I2C interfaces

by AbnerW on Tue Aug 13, 2019 4:51 am

Hi,

I can see this product has two I2C interface for touch. And in our board one I2C(call it No.1) interface is used by UART, but in hardware we do not block it with the screen I2C interface. So when I use another I2C(call it no.2) to control touch panel, some UART data is still in the I2C No.1 pins. It seems will result in issue. So any software ways to avoid this? When I use No.2 I2C, the screen touch can ignore the data from No.1 I2C. If not I think we should change the hardware.

Best Regards.
Abner

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Re: 2.8" TFT Touch Shield Cap two I2C interfaces

by adafruit_support_mike on Wed Aug 14, 2019 1:41 am

The TFT Touch Shield is designed to fit the Arduino Uno R3 GPIO headers, which connect one I2C interface to two different sets of pins.

The old/original I2C pins are A4 and A5, but the R3 Uno added another two pins near the USB jack specifically for the SDA and SCL signals. Those pins are connected to A4 and A5 on the Uno and on the TFT Touch Shield, but the Shield has jumpers you can cut to break that connection if necessary.

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Please be positive and constructive with your questions and comments.