3-36
MPC106 PCIB/MC User's Manual
MOTOROLA
3.2.6 Memory Interface Configuration Registers
The memory interface configuration registers (MICRs) control memory boundaries
(starting and ending addresses), memory bank enables, memory timing, and external
memory buffers. Initialization software must program the MICRs at power-on reset and
then enable the memory interface on the MPC106 by setting the MEMGO bit in memory
control configuration register 1 (MCCR1).
3.2.6.1 Memory Boundary Registers
The extended starting address and the starting address registers are used to define the lower
address boundary for each memory bank. The lower boundary is determined by the
following formula:
Lower boundary for bank
n
= 0b00 || <extended starting address
n
> || <starting
address
n
> || 0x00000.
The extended ending address and the ending address registers are used to define the upper
address boundary for each memory bank. The upper boundary is determined by the
following formula:
Upper boundary for bank
n
= 0b00 || <extended ending address
n
> || <ending
address
n
> || 0xFFFFF.
See Figure 3-21, Figure 3-22, and Table 3-25 for memory starting address register 1 and 2
bit settings.
Figure 3-21. Memory Starting Address Register 1—0x80
Table 3-24. Bit Settings for 60x/PCI Error Address Register—0xC8
Bit
Name
Reset
Value
Description
31–24
Error address
0x00
A[24–31] or AD[7–0] (dependent upon whether the error is a 60x bus
error or a PCI bus error). When an error is detected, these bits are
latched until all error flags are cleared.
23–16
0x00
A[16–23] or AD[15–8] (dependent upon whether the error is a 60x
bus error or a PCI bus error). When an error is detected, these bits
are latched until all error flags are cleared.
15–8
0x00
A[8–15] or AD[23–16] (dependent upon whether the error is a 60x
bus error or a PCI bus error). When an error is detected, these bits
are latched until all error flags are cleared.
7–0
0x00
A[0–7] or AD[31–24] (dependent upon whether the error is a 60x bus
error or a PCI bus error). When an error is detected, these bits are
latched until all error flags are cleared.
31
24 23
16 15
8
7
0
Starting Address Bank 3 Starting Address Bank 2 Starting Address Bank 1 Starting Address Bank 0