I want a mode of HCS12 to have the following configuration:
1- Use the internal memory map including registers, eeprom, ram and a part of (no)banked-flash, as in normal single chip.
2- Add an external parallel RAM device, for example 1 Megabyte (20 bits) for aquisition data storage.
3- Add an external parallel peripheral such an ADConverter, 12 bits resolution .
The control of these elements must be done by external bus, not by I/O ports.
The internal flash must visible for loading and execution program .
I read very quicly appliaction note AN2408, is it a good beginning?