Now I'm doing a project using a evaluation board coming from keil software,Dallas 80C320. Here is my program configuration
EPROM : start from 0x100, length 0x4EFF
XDATA : start from 0x5000, length 0xAF1F

Memory architecture : von Neumann/HIROM
address 0000h-7fffh from EPROM are mapped to CODE 8000h-ffffh
address 0000h-7fffh from RAM are mapped to CODE and XDATA 0000h-7fffh
address 8000h-ffffh from RAM are mapped to XDATA 8000h-ffffh

When I using the MON51 shipped with the board to download the program into the RAM of the board, it works well.But when I burn the code into a EPROM ( without MON51), it doesn't work at all.
Did I get something wrong or missing ?

And, I also have some stupid questions:
1 If I burn the code in the EPROM and place it in the evaluation board, do I still need the RAM on the board since the program has resided in the EPROM?

2 When refers to external memory, does it mean RAM or EPROM ? Or the memory physically located externally from the 8051 CPU?

3 Does CODE memory mean EPROM or RAM ( in the case code resides in the EPROM ) ?

Thanks