Well, I'm getting old, and as you surely know, we old guys tend be get used to our own ways of doing things! http://www.picbasic.co.uk/forum/images/smilies/wink.gif

Thank you a lot for all your help, but it simply seems too complicate to have all that looooong assembly code put in, just to do one single division! Reconfiguring my PC to be able to install PBP in the default configuration, and then learning to use the new programs, and so on, would simply take FAR too long. I want to get my project going soon, instead of embarking in a new project of PC reconfiguration, learning to use a new programming environment, and who knows what else.

So I have totally turned around the way I calculate the value I need. Instead of the routine that required the 64 bit division to arrive at the final 32 bit tuning value I need for my DDS, I prepare the data in 16 bit chunks and calculate the 32 bit tuning value as the last step in the process, using PBP's "*" and "**" operators. In doing so, I loose some tuning range, and some tuning resolution, compared to the method that needs the 64 bit division. But both of these losses are acceptable for this particular project, so I will keep this for now.

In the future I will probably do more demanding projects using a DDS, and at that point I will get back to needing multibit division... But based on the newly acquired experience, I will then use an 18-series PIC, so I can use PBP's 32 bit math, which should allow enough tuning range and resolution for even quite high requirements, using the same algorithm I implemented a while ago.

By the way, the configuration of my PC has evolved from the very first PC I owned, almost 30 years ago, and that's why it doesn't conform to modern Windows practice. I use a large quantity of specific programs , many of them written by myself. Over the years, I have added to this setup, and transferred it from each PC to the next more modern one.

Any attempts I have done to set up a new system on a new PC, and getting everything to work there, have proven to take so much time that I threw the towel before getting anywhere close to finishing. That's why I still use my old configuration.

Thanks again. I have learned that apparently there is no simple way to use PBP's 16 bit math to create 32 or 64 bit math, and so it's better for me to use a workaround.