PD77210_15 Datasheet, PDF (36/76 Pages) Renesas Technology Corp – 16-BIT FIXED-POINT DIGITAL SIGNAL PROCESSOR

µPD77210, 77213
7.2 Data Memory
7.2.1 Data memory map
The data memory space consists of two planes: the X and Y memory spaces, each of which consists of 64
Kwords × 16 bits. The area of 0x8000 to 0xFFFF is a paging area that supports a memory space of 64 Kwords or
more by specifying a page by using the data paging register (DPR). The DPR can be set in the same manner
regardless of whether the X or Y memory space is accessed.
Page 0x3F of DPR is a window to the external data memory. The Data ROM of the µPD77213 exists in the
paging area and is accessed as DPR=0x0.
Page 0x80 of the DPR is shared by 0x0000 to 0x7FFF of the internal instruction RAM. The lower 16 bits of the
32-bit instruction RAM constitute the X data memory, while the higher 16 bits are the Y data memory.
Because some pins of the µPD77213 are shared with the SD card interface, the area that can be accessed when
the SD card interface is being used is restricted. The address pins MA13 to MA19 are shared with the SD card
interface. When the SD card interface is being used, therefore, only the 13-bit address area of MA0 to MA12 (8
Kwords) can be accessed.
0xFFFF
µ PD77210
Paging area
0xFFFF
µ PD77213
Paging area
Paging area^{Note 1}
(32 Kwords)
External data
memory window
(32 Kwords)
Paging area
(32 Kwords)
Data ROM^{Note 2}
(32 Kwords)
External data
memory window
(32 Kwords)
0x8000
0x7FFF
0x4000
0x3FFF
0x3800
0x37FF
0x0000
Data RAM
(16 Kwords)
Peripheral
(2 Kwords)
Data RAM
(14 Kwords)
(DPR=0x3F)
0x8000
0x7FFF
0x5000
0x4FFF
0x4000
0x3FFF
0x3800
0x37FF
0x0000
System
Data RAM
(4 Kwords)
Peripheral
(2 Kwords)
Data RAM
(14 Kwords)
(DPR=0x0)
(DPR=0x3F)
Notes 1. If the paging register is set to a value other than 0x3F (external data memory window) or 0x80 (internal
instruction RAM area), programs and data cannot be stored to the addresses of the paging area, nor
can these addresses be accessed.
2. The higher 8 words of the data ROM (0xFFF8 to 0xFFFF) constitute system area.
Caution Programs and data cannot be allocated to the system area, and neither can it be accessed. If
these addresses are accessed, correct operation of the device is not guaranteed.
A paging area in which no DPR page exists cannot be accessed. If this kind of paging area is
accessed, correct operation of the device is not guaranteed.
34
Data Sheet U15203EJ3V0DS