8051MX (for "Memory eXtended") is an extension of the 8051 made by Philips.

It can use 3-byte addresses, thanks to a "EPTR" register and using the A5 instruction. But it can also work exactly as a standard 8051.

Most tools (compilers, RTOSs, etc.) that work on the 8051 have been adapted in order to work for the MX. One of my tasks has been to port the Raisonance 8051 RTOS to the MX.




Well, I have many, but I'm not allowed to speak about them. :)

More seriously, you just need to look at the examples given with a RTOS and you'll see that if you had had to write the same thing without the RTOS, it would have taken much longer. And if you happen to need to modify it several months later, then the gain is even more. At least for our examples it's quite obvious. I don't know about our competitors, but I guess that it's the same.

My experience is that RTOS is great for team work. It's usually easier to split tasks and makes maintenance easier.


Now, some of our customers have been using our 8051 RTOS for more than ten years on several different projects, and I guess that if it wasn't interesting, they'd stop doing it. They are people who know the 8051 very well, they would know how to do anything in assembler, or in C but without RTOS, but they choose to use C and a RTOS. It just makes their life simpler.


Vincent