Hi

I am interested in building, and programming a Motorola 68HC05 family micro-controller circuit on a breadboard. Have any of you tried this ? Could you kindly suggest what would be a good chip to use, or pointers to online resources/circuit diagrams. Clearly it makes no sense to try using a one time programmable device.

I found a HC05 port of the GNU toolchain which I plan to use for writing and building the programs (using Linux). Though I am not sure how they are loaded onto the chip.

I realise these chips are obsolete and I am better off spending my time on AVRs and PICs but I am still interested.

regards
thomas

 

The Motorla 68HC05 has been around for many years and has spawned many new families.
That division of the company is now called Freescale Semiconductor.

http://www.freescale.com/

Rather than going back to an obsolete 68HC05 chip I would suggest using something from the MC9S08 family.

You can purchase a demo kit similar to something like this that comes with development software:

http://www.digikey.com/product-detail/en/DEMO9RS08KA2/DEMO9RS08KA2-ND/1089998

What is your reason for selecting the Motorola/Freescale 68HC05?

 

I would like to have a customizable circuit to learn interfacing and programming it while reading http://www.freescale.com/files/microcontrollers/doc/ref_manual/M68HC05TB.pdf

I did see http://www.evbplus.com/Dragonfly12P_9s12/DIP40_9s12.html that fits on a breadboard but was not sure if that would be a good choice to accompany the above document that I have started reading (it is cited many places online, as worth reading ).

 

That HC05 is an excellent document and is usually my first choice when recommending a text for someone new to microcontrollers.

The HC05 instruction set is the forerunner of many Freescale microcontrollers. Hence it is the basis for many of the newer families. You should be able to pickup the same programming techniques using the 9S08, HC11 and HC12 families.

Check out this site:

http://www.technologicalarts.com/

 

This demo board for 9S08QG8 is still available:

http://www.digikey.com/product-detail/en/DEMO9S08QG8E/DEMO9S08QG8E-ND/1227816

 

I would suggest you take a look at this site

http://www.sparetimelabs.com/funwith08/funwith08.php

I have a lot of programmed 68HC05 chips from the obsolete line interface circuit cards of a telephone exchange. But I cannot make use of them at all. If you have access to the UV version of 68HC705 you can program and erase it for many times.

From another forum, I was told that It is also not usable by connecting external RAM and EPROM like the 8051. So I think the best you can do now is to play with the 68HC908 which is flash based. And if I'm not mistaken, it supports bootloader on RS232 and USB on the 20 pin DIP 908.

Allen