TC1796
System Units (Vol. 1 of 2)
CPU Subsystem
User’s Manual
2-31
V2.0, 2007-07
CPU, V2.0
2.6
Data Memory Interface (DMI)
Figure 2-13 DMI Block Diagrams
2.6.1
DMI Features
The Data Memory Interface (DMI) has the following features:
•
64 Kbyte data memory:
– 8 Kbyte Dual-Port data memory (DPRAM), accessible from CPU and Remote
Peripheral Bus
– 56 Kbyte local data memory (LDRAM)
– DPRAM and LDRAM are parity protected
•
CPU interface:
– Supporting unaligned accesses (16-bit aligned) with a minimum penalty of one
cycle for unaligned accesses crossing 2 lines
•
Data Local Memory Bus (DLMB) interface. Allows access to the rest of the system.
8 KB
DPRAM
CP
U
In
te
rf
ac
e
DMI
Control
Registers
MCB05597
To/From Data
Local Memory Bus
128
Data Switch
&
Data Alignment
&
Interface Control
64
DLMB Interface
Slave
Master
128
56 KB
LDRAM
BPI
In
ter
fa
c
e
To/From
Remote
Periphera
Interface
Bus
(RPB)
Data Memory
Interface (DMI)
DMEM
DMEM
= Data Memory in DMI
LDRAM = Local Data RAM
DPRAM = Dual-Port RAM
DLMB
= Data Local Memory Bus
128
128
32
32
Parity
Control/Check
To SCU (DMI Memory
Parity Errors)