View unanswered posts | View active topics It is currently Sat Sep 26, 2020 8:42 am

Reply to topic  [ 3 posts ] 
Clarification on I2C memory address vs register 
Author Message
User avatar

Joined: Sun Aug 19, 2007 2:43 pm
Posts: 156
Location: New Jersey
Post Clarification on I2C memory address vs register

I just want to make sure I understand the terminology here.

With my little understanding about "a register", it is indeed memory address; has 2 kinds of memory data register and memory address register. However, it is not something user level code can modify like these I2C unique address, command address, etc. However, I kept reading they were referenced as registers. Thus, I am bit confused here. Could someone clarify that for me?

==Elizabeth Mabrey

Sun Jul 27, 2014 12:22 pm
Profile WWW
Site Admin
Site Admin
User avatar

Joined: Wed Mar 05, 2008 8:14 am
Posts: 3654
Location: Rotterdam, The Netherlands
Post Re: Clarification on I2C memory address vs register
Register and memory address are often used fairly interchangeably. I would use register for I2C, since I would consider memory address something in the RAM of the chip. The register is what you access through the I2C command and might not really be a memory address at all, but rather a trigger to do perform an action, like "start calibration".


| Professional Conduit of Reasonableness
| (Title bestowed upon on the 8th day of November, 2013)
| My Blog: I'd Rather Be Building Robots
| ROBOTC 3rd Party Driver Suite: [Project Page]

Sun Jul 27, 2014 1:59 pm
Profile WWW

Joined: Tue Dec 11, 2012 9:19 pm
Posts: 58
Post Re: Clarification on I2C memory address vs register
Xander is correct, and in fact, PMBus, a specification for power supply
management over I2C, specifically avoids the term "register" in favor
of "command" to avoid just this kind of confusion.

When you perform an I2C transaction you are really just sending a
number over to a slave device, and then writing or reading some data.
That number may be an offset in a device's memory, or it may be
something to be interpreted by a slave device that's running software itself.

Mon Aug 04, 2014 5:13 pm
Display posts from previous:  Sort by  
Reply to topic   [ 3 posts ] 

Who is online

Users browsing this forum: No registered users and 2 guests

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  

Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group.
Designed by ST Software for PTF.