TCAL6416: Hiz mode

Hi Fred,

Once a I/O pin is configured as an OUTPUT through the configuration register, it outputs a HIGH or LOW logic level depending on the output port register value. 

If you want high-z, then convert the I/O to an INPUT through the configuration register. This makes the pin a true high-z CMOS input. 

Regards,

Tyler

Hi Fred,

If a Pxx pin is configured to OUTPUT, it only has two states, drive HIGH or drive LOW. There is no tri-state on a pin that is configured to OUTPUT. 

To get a tri-state on the Pxx pin, configure the OUTPUT back to a CMOS high-z input with a external pull-up or pull-down resistor, or configure the internal PU/PD resistors through the registers. 

Regards,

Tyler

Hi Fred,

Fred Cheng said:

so you mean set Hiz input with external pull-up as steady state or default , and change command to turn it to LOW when needed?

What you described here is similar to an open-drain output. 

Set high-z INPUT with external pull-up as steady state. (this is the logic high through the PU resistor to VCC).

Change command to turn it to OUTPUT LOW - this converts the I/O to an OUTPUT, and pulls it LOW. 

Regards,

Tyler