you keep persisting with referring to the ancient schematic and code you have.

the ancient schematic and code you refer to is MMIO (memory mapped I/O) and the uC you use have no external memory. Thus, there is no way in hades you can mangle it to work.

THROW IT AWAY NOW

Then, go get a cup of coffee, or whatever you need, to clear your head of everything you remember from that ancient design.

Then, and only then, get the datasheet for an Optrex LCD similar to the one you have (except for pinning all Hitachi based LCDs are the same, and the Optrex datasheets are the best) study it and get an idea (there are even flowcharts in the datasheet.

Then, and only then, write the necessary code yourself

If in that process some specific questions come up, ask them here.

So called "reference designs and reference code" can be helpful, but starting with them whith no basic knowledge does NOT work.

Erik

PS were you to use a derivative with external memory access the ancient stuff you have "would work", however be grossly inefficient with a modern derivative.