6805 EVM boards Off Topic sorry

It is not off-topic, so no need to apologize. But I am afraid I haven't use the chip, so I can't help.

Hi,

It's not off topic at all here !

Your customer has an old project to change you say ; so it needs a preliminary study to verify if modern microcontrollers could fit the requirements and i'm sure it will. But ...

But software tools side remains THE criteria of choose.

I have extensive experience with architectures based on stm32, avr32, avr at(x)mega ... etc. All are supported by gcc, gdb, jtag(openocd) which are very productive under the GNU/Linux dev platform.

OTH, H.

H.

Am 05.10.2017 21:45, schrieb Walter Banks:

Apart from the "E" all popular 68HC05 were EPROM-OTPs. So he needs windowed EPROM-parts and a programmer. That was the low cost "Motorola M68HC05 EVM" emulator:

The alternative were very low cost boards for specific types like "C" "B" that were pretty useless for emulation but usable for programming. He would need to specify which type he uses.

The real answer ( no customer wants to hear ) is of course: porting to something modern will be cheaper in the long run.

MfG JRD

Thanks all. He is using 68HC05C8's BTW. Another old customer saw the post and emailed me about an EVM board he has. The old EVM board is about all that is needed in this case.

Porting to something modern is not always the cheaper or best solution but often is. This is one of those cases.

Over the last few years I have seen some other cases where porting old 8 bit applications to 32 bit general purpose processors has not worked very well. The issue in several cases has been the difference in generated emi between processor 8 and 32 bit data streams inside the processor. We had several old customers that had re-developed old projects around the same time and contacted us about problems they were having. Initially I assumed that it was an experience issue with a different technology. I was at a trade show a few weeks later and an friend who specializes in board layout and emi minimization opened a conversation over lunch making similar comments with the internal radiation comment as the cause.

w..

I'd expect the more modern CPUs to have typically have considerable lower emitted noise, but at a higher frequency.

Yes and No, as the old device is probably sub 10MHz and the new device has at least four times as many transmitters at same time, running internally at least at probably greater than 30Mz.

The levels of radiation at the higher harmonics will change compared to older base frequency, and more lower power transmitters may well be higher radiation then the 5th or higher harmonic of the original.

Then it depends if the rest of the system is affected by higher harmonics.