Examples of Memory MAP with 2x Clonix-D?

[MeindertKuipers]

(09-28-2022 03:24 PM)floppy Wrote:  My thoughts.. When a ROM is created (for bank switching), then it uses most likely (sorry, I dont know how to read ROMs so far) a relative jump?. So, if a ROM is placed at page 5 (Bank1), it will spread around the memory from the start address of that page?
I am not sure if all ROMs are using relative jumps and accepting page MOD 2 not zero. According Ange, Sandmath start its paging only at 8 or 10 or 12 or 14. Why is this? I would like to know the background of this and the details of "is normally"

When a ROM is placed in Page 5 (which is not a good example in a 41CX, but possible in a HP41) its address range is from 0x5000 to 0x5FFF. And unless it is for a very specific purpose with a fixed page address (like the printer or a Page 4 ROM) any ROM, bankswitching or not, should be written with relative jumps only, independent from odd or even pages. This makes the ROM transparant to use in any hardware environment (MLDL2000, 41CL, NoVRAM, DM41X).

The 'normal' bankswitching may limit the behavior above when it is a 2-page ROM and depends on switching banks in both pages at the same time. And this does depend on the hardware platform as some of us had to learn the hard way.