TCAL6416R: TCAL6416R GPIO default output setting questions

Hello Roy,

To keep the example code simple, I will not include the target address and auto-increment.

I will be using the following I2C word format:

At start-up, all I/O ports will be in a Hi-Z state. To output a logic low, you will need:

• 1) Send all zeros to the Configuration 0/1 registers
• 2) Send all zeros to the Output Port 0/1 registers

The following code will force Port 0 to output logic low

0x06 00
// 0x06 is the Configuration 0 register address while 0x00 is the data we write to the register. Writing data 0x00 changes Port 0 from an input to an output (this applies to all I/Os under Port 0)

0x02 00
// 0x02 is the Output Port 0 register address while 0x00 is the data we write to the register. Writing data 0x00 forces Port 0 to output a logic low (this applies to all I/Os under Port 0)

If you want to accomplish the same thing for Port 1, you need the following code:

0x07 00
0x03 00

Regards,

Josh