
LH77790B User
’
s Guide
Memory Map and Register Summary
19-3
System Configuration Region
This 24KB region is dedicated for System Configuration Registers and should not be mapped
to external devices. Even though the region is partially assigned, future embedded microcon-
trollers will use unassigned memory for future system configuration registers. This region can
be included as part of any of the eight segments (segments 0-7) or default segment. Only the
privilege bits (SPR, UPR) from the SDR for that segment are recognized when an address
belongs to this region of 24KB. Other bits like BSEL, C and HW are ignored for addresses in
this region only. This gives the system designer the flexibility to assign a privilege to this region.
This region is reserved for the following System Configuration registers:
Segment Descriptor Registers (SDRs)
START/STOP Registers
Bank Configuration Registers (BCRs)
DRAM Refresh Register (DRR)
Cache Control Registers (CCRs)
Local SRAM Control Registers (LSCRs)
Identification Register (IDR)
I/O Configuration Registers (IOCRs)
LCD Bit Control Register (LCD_BITCTL)
Interrupt Controller Registers
Clock and Power Management Registers
Watchdog Timer Registers
Internal Peripherals Region
This 40KB region is dedicated for internal peripheral registers and should not be mapped to
external devices. Even though the region is partially assigned, future embedded microcon-
trollers will use unassigned memory for future peripheral registers. This region can be
included as part of any of the eight segments (segments 0 - 7) or it will use the default seg-
ment. Only the privilege bits (SPR, UPR) from the SDR for that segment are recognized
when an address belongs to this region (40KB). Other bits like BSEL, C and HW are ignored
for addresses in this region only. This gives the system designer the flexibility to assign a
privilege to this region. The base address for each group will be on a 1KB boundary.
Cache Region
When the Cache is operating in SRAM mode, the Data RAM (512 words) will map to
address locations 60000800-60000FFF. In the SRAM mode, the cache can be included as
part of any of the eight segments (segments 0 - 7) or it will use the default segment. Only
the privilege bits (SPR, UPR) from the SDR for that segment are recognized when an
address belongs to this region.
Local SRAM Region
The local SRAM can be programmed to map to two different regions. The mapping is con-
trolled by the Local SRAM Control Register (LSCR) as discussed in the local SRAM section.
Mapping the local SRAM to the lower region allows the exception vectors to be mapped to
the local SRAM for faster access. This region can be included as part of any of the eight seg-
ments (segments 0 - 7) or it will use the default segment. Only the privilege bits (SPR, UPR)
from the SDR for that segment are recognized when an address belongs to this region.