37
3
CHAPTER 3 CPU FUNCTION
3.1 MEMORY SPACE
The
µ
PD78214 can access a memory space of up to 1M byte. Figs. 3-1 to 3-4 show the corresponding memory
maps. The mapping of program memory depends on the status of the EA pin. The EA pin of the
µ
PD78213 must
be tied low.
(1)
µ
PD78212
Program memory is mapped to the internal ROM (8K bytes: 00000H to 01FFFH) and external memory (56704
bytes: 02000H to 0FD7FH). External memory is accessed in external memory expansion mode. The area
mapped as external memory can also be used as data memory.
Data memory is mapped to internal RAM (384 bytes: 0FD80H to 0FEFFH). In 1M-byte expansion mode,
external memory (960K bytes: 10000H to FFFFFH) is mapped as expanded data memory.
(2)
µ
PD78213
Program memory is mapped to external memory (64768 bytes: 00000H to 0FCFFH). This area can also be used
as data memory.
Data memory is mapped to internal RAM (512 bytes: 0FD00H to 0FEFFH). In 1M-byte expansion mode,
external memory (960K bytes: 10000H to FFFFFH) is mapped as expanded data memory.
(3)
µ
PD78214,
µ
PD78P214
Program memory is mapped to internal ROM (16K bytes: 00000H to 03FFFH) and external memory (48384
bytes: 04000H to 0FCFFH). External memory is accessed in external memory expansion mode. The area
mapped as external memory can also be used as data memory.
Data memory is mapped to internal RAM (512 bytes: 0FD00H to 0FEFFH). In 1M-byte expansion mode,
external memory (960K bytes: 10000H to FFFFFH) is mapped as expanded data memory.
Содержание PD78212
Страница 11: ......
Страница 53: ...24 ...
Страница 61: ...32 µPD78214 Sub Series 9 VSS Ground 10 NC non connection Not connected inside the chip ...
Страница 65: ...36 ...
Страница 83: ...54 ...
Страница 135: ...106 ...
Страница 271: ...242 ...
Страница 405: ...376 ...
Страница 417: ...388 ...
Страница 423: ...394 ...
Страница 449: ...420 ...
Страница 457: ...428 ...
Страница 471: ...442 ...
Страница 487: ...458 ...