Hello. I am new to this community and I hope you can help me with my problem. I need to make a C application for winbond w78c438 but that chip is not natively supported by any compiler ...however...some degree of support can be found in KEIL ...my problem is that I need to tell to the compiler that addresable memory space is 20 bits long...and the register in which the upper 4 address bits reside is at address 0xA2... I've modified one of the *.h files in order to add this feature but I'm still getting errors about pointers... Please advise... Thanks
Read up on code banking and on xdata banking. Without native support for that chip, that's as close as you're likely to get to exploiting these features easily.
What exactly do you want ot do with the extended memory? If it's just something simple, with only occasional bank switches, maybe you could just write your own 'C' function to switch banks? This has worked for me on some Triscend projects...