Success at last
I was finally able to boot ProDOS! The big holdup seemed to be the floppy emulation. As soon as I disabled the floppy ROM, it booted into ProDOS and the basic interpreter. ProDOS seems to do something with the floppy even though it is not the boot drive. ProDOS also sees the extra 64K of memory and sets up a RAM drive. I am trying to decide what to do with the extra 384K of RAM. Originally I was going to set it up as another RAM drive, but I have been thinking of setting it up as additional banks of memory like the RAMWORKS card. I maybe forced to do the additional banks because of CPLD space. It is getting pretty tight.
The next task is to debug the floppy. Hopefully it will not be too hard. I will need to get a little more familiar with the floppy interface to do the debug. When I wrote the code, I did it quickly, so I know there is some things wrong. The main thing I have to learn is what does the floppy look like when it is unformatted. Right now I did not make any allowances for an unformatted disk. But maybe I do not need to know. There could be something else that ProDOS is looking for.