Legacy Z80 meets AVR

[SiliconWizard]

I hear what you  say but legacy cpu's do have a place, they are Von Neumann mpu's which renders the added flexibility to run your code from ram, i.e., you can't run cpm on an AVR or a 8051 even if the instruction sets were all the same.

You can make 8051 easily to work as a von Neumann. Just wire together XCODE and XDATA into the same physical memory.

Yup! There are tricks!

This actually was/is a very common setup for many 8051-based systems. Nothing special.

[bson]

there was not even a standard format to move a file from one CP/M to another.

Ah yes, I had forgot all about using kermit to transfer files between systems...

[westfw]

there was not even a standard format to move a file from one CP/M to another.

IIRC, the CP/M "File System" was a lot more standardized than floppy formats of the day.  Especially 5inch floppy formats; I purchased a number of CP/M products on 8inch floppys that were pretty much expected to be readable on any CP/M system with an 8inch drive.  (OTOH, that might have been because they had their own BDOS in a boot sector or something...)

[rstofer]

there was not even a standard format to move a file from one CP/M to another.

Ah yes, I had forgot all about using kermit to transfer files between systems...

I forgot how I did it but you can imagine the problem of getting CP/M from a machine with an 8" Floppy onto an FPGA incantation with a Compact Flash.  Kermit was definitely involved in the later stages.

Actually, using something like Linux' dd command might have been a great help.  I have used that approach with later projects.

[ale500]

CP/M disks have 128 byte sectors, if one could write its own BDOS, why nobody is using 512 byte sectors (I mean nowadays that compact flash and SD cards are the choice) ? I haven't read enough about CP/M yet, maybe the answer is very obvious, and in front of me....