Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
The Coldfire family has a few different varieties of cores. The different cores are called V1, V2, V3 and V4. V1 is the most simple core, where V4 is the most complex. I have the most experience with the V2 cores. They are truly great processors, especially if you need to have a low power network enabled device. For a good brief about the core architecture look at the third chapter of any of the processors reference manuals... here is the MCF5271RM:
**broken link removed**
Keep in mind this will vary quite a bit between core families, especially the internal buses and cache.
ColdFire processors work great for network products because the core is big endian. Since all network traffic is big endian you do not need to reorder all the network data like you must do on most many other embedded 32-bit devices. Since these are mostly 50-200MHz devices, it is hard enough to saturate full network speed without reordering all the data.
The Coldfire family also shares many of the same peripherals between processors so it is easy to port drivers between them. They have a very nice queued SPI peripheral that is very fast... except it cant do slave mode SPI. Some devices such as the MCF5234 include a really nice eTPU peripheral which is unique to Freescale's processors. The eTPU is a seperate CPU that is dedicated to performing complex timing operations. These channels can be used for anything from UARTs to complex motor controllers... You can easily run all the timings in a fuel injection engine with the functions they provide for this peripheral.
Most of the Coldfire devices are micro-processors not micro-controllers. The big difference is they do not have embedded flash memory and require external flash to load code from. They are steadily increasing their microcontroller market but for any powerful embedded network device you will want to have more external RAM for buffers, 64K gets a little tight especially for WAN traffic.
I am a design Engineer for a company called NetBurner that sells Coldfire based modules. We also provide all the software and tools you will need for embedded network applications. A single $99 dollar dev kit will get you all the software, hardware and tools required to bring your embedded network design to life. I am a bit biased since I work for the company but take a look at the NetBurner forum and I am sure you will see that the our customer satisfaction is pretty high. With our MOD5270 (150MHz Coldfire) I have been able to sustain 90+ mbit transfers when sending UDP data, a little over 60mbit data throughput for TCP sockets. Not bad for a device that consumes less then 1watt at full network speeds, with more then 50% of this power is due to power drawn by the Ethernet PHY.