HC12 (+ Ethernet) development kit ?

Why not the NE64 version of the HC12? It has ethernet built in. Digikey as a demo board for $85.

Dave Rooney

If the application is growing out of the 64k address space, the 6812 family does not seem to be the right choice.

The one with NE64 controller, if the Ethernet is required.

IAR is a hassle if you have to go beyond the 64k boundary. Cosmic is much more flexible and simpler.

Vladimir Vassilevsky

DSP and Mixed Signal Design Consultant

I agree with the other posters that you want an NE64.

For an IDE, most Freescale developers now are using CodeWarrior. It may not be the best in every way, but it's clearly more popular than the others by a factor of 10 or more.

I make an open source IDE for gcc for this platform, but it seems to me that you want a commercial solution. The commercial solutions have C source level debugging that isn't very good yet in the open source tools.

You will need a BDM device from P&E micro. Also, make sure your NE64 board has a BDM connector on it. Some cheap boards may not have this, since the NE64 comes with a serial monitor.

Eric

Hey thanks Dave, I didn't know FreeScale made such a chip !

For those who may be interrested here's a link to the MC9S12NE64 summary :

And of course, they have a MC9S12NE64 evaluation kit :

However, my application requires that the MCU processes the data coming from an ADC, I am wondering if the MC9S12NE64 could handle the Ethernet side while keeping enough speed for the other tasks. Unfortunately I do not yet have the specifications of the data flow speed from the ADC to the MCU, so I thought it would be safer for now to have two separate chips. But does it make sense since the Ethernet controller chip should be handled by the MCU to process the Ethernet transmission ?

An internal MAC is always faster to access and has far less overhead than an external chip connected via SPI or io ports. I'd choose the integrated solution if possible.

Mit freundlichen Grüßen

Frank-Christian Krügel

I think it would be safer in this situation to have everything on one chip. Freescale has already spent the time to optimize the interface on the NE64. IIRC when ethernet is sending or receiving the SRAM databus multiplexes every-other cycle between CPU and ethernet.

You are not going to bit-bang the ethernet so unless you have totally separate CPUs for each of ethernet and A/D it makes most sense to have both as close as possible.

There *are* external TCP/IP ethernet modules little bigger than an RJ45 socket. But about $100 each.

as far as I know it's not the efficient way to connect a Freescale chip to Ethernet.

Coldfire seems to be better suited.

Oliver

What do you feel is inefficient about the NE64? If an HCS12 processor is suitable for your application, it is a great choice.

Yes, there is a Coldfire part with built in MAC/PHY - the MCF5223x family. Unfortunately it's still new enough that you can't get it from Digikey, etc. (I did finally get samples from our distributor though). Also, the BDM pod costs substantially more and is a 26-pin connector vs. 6 pin for the HCS12 family.

In short, we'll be generally staying with the NE64 and the benefits of our experience with it, except for one application that needs more ram.

Another way to view it: if you are using ethernet to do things that could be done on over fast RS232 but simply need to be ethernet for some reason, the NE64 is great. If you want to build an embedded server that's going to do something more complicated, look at the Coldfire parts.

computing power. Future of the device.

IIRC, on a busy network, the poor S12 can get heavily loaded.

It's o.k. to _stay_ but I wouldn't start a new product with it.

Oliver

By staying with it, we will be starting numerous new products with it. It works and we know how to use it.

Agreed, the part is a dead end. If future versions of your product require more or less capability then you will be forced into a painful move to another part.

Only if there are a lot of Windows machines kicking up their usual broadcast storms. Only broadcast packets and packets addressed to your MAC address will get the attention of the CPU.

Almost 2 years ago I did start a new product with it. Last I heard it still has not shipped. Not an NE64 problem, but one of the problems that caused me to leave.

At the time Coldfire was promising similar solutions but uncertain delivery, couldn't wait. One chip with SRAM, FLASH, MAC + PHY was what the NE64 offered. Atmel's SAM7X, ARM with ethernet, was another attractive option that is now shipping.

I wasn't terribly happy with Freescale's "free TCP/IP protocol stack." Sloppy code ported from an 8 bit implementation where the MAC was hanging off I/O ports.