16-bit I2C addressing?

Doug McKenney

Other Parts Discussed in Thread: TCA9548A

We need more that 10 bits of address for our custom sensor chip. We may have up to 64K of them in a system. We'll be using a lot of TI chips - extenders, repeaters, hubs, etc. The I2C standard only allows 7 or 10 bit addressing. I need some ideas to enable 16-bit addressing in I2C. Any ideas out there?

over 14 years ago

0 Jonathan Valdez over 10 years ago

TI__Genius 16510 points

Hello Doug,

Per the I2C spec, 16-bit addressing is not allowed.

The closest approach to having many different sensors on a bus is using a large number of switches such as the TCA9548A (possibly cascaded), to have multiple layers of the I2C tree. This is not a direct 16-bit approach, but you can enable and disable a series of switches to route to the sensors that you wish to connect to.

0 Doug McKenney over 10 years ago in reply to Jonathan Valdez

Prodigy 90 points

Jonathan,

Thanks for your help. I appreciate it (even 4 years later!)

Doug

0 Jonathan Valdez over 10 years ago in reply to Doug McKenney

TI__Genius 16510 points

Yea, I realize it's late. Now that I am responsible for this forum, I am going through and answering any open questions I can, even if they were created long before I came along. At least anyone that searches online might find some use.

If you have any future questions, please don't hesitate to post in this forum, knowing that you will get an answer.

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16-bit I2C addressing?