Why the OS in a small device is different than the PC

Kyle — Thu, 28 Dec 2006 19:24:09 +0000

I’m continually amazed at the analogies between the PC and a handset. Most of the time, the phone will not be used like your PC. I’ll discuss several topics in future posts, for now, let’s focus on the interface of the machines. On the PC, the interface consists of a keyboard and a mouse/ trackball.
On the handset, you’ve got multiple buttons to issue commands. However, the keyboard and the mouse have the unique quality of being ubiquitous. Everyone that has a computer has a mouse and/or a keyboard. When I move over to a handset, that changes.

I may have a keyboard on my phone. In fact, I may have one of several different versions of a keyboard, which is even more frustrating. Further, there are several additional buttons on the phones that aren’t on a PC, and these buttons change from phone to phone. So, depending on my phone, the behavior of the little side button may or may not perform the same function.

How does this translate back to the operating system? Well, the PC operating systems can expect a keyboard and mouse. They can consolidate all input to those 2 mechanisms. Handset operating systems can expect a bevy of buttons. And, those buttons will all work differently on different phones.

This variety is havoc on device drivers and upper layer protocols, who may have to deal with several I/O sources. The device driver software then has to tie-in with the semiconductor interrupt controller and also with the specifics of the I/O functionality.

That’s quite a big difference from my view. When you consider that software complexity is driving BOM costs, mucking with the device driver and interrupt controllers are 2 sure-fire ways to add to your workload.

Are we missing the point?

Kyle — Mon, 31 Jul 2006 01:12:35 +0000

There is much talk in the media and on the web about the ‘latest’ cell phone features and functionality. News seems to continually roll across the wire proclaiming the new phone that will be all the rage. These high end phones are all the rage for marketers.
In fact, the high-end ‘smartphone’ only accounts for around 5%-10% of the total volume of phones. If you want to know where the market is going, sit in a mall (outside of Silicon Valley) and watch how people use their phone. That’s where the real users are.

Small Devices

Why the OS in a small device is different than the PC

Are we missing the point?