ez80l92 ZiLOG Semiconductor, ez80l92 Datasheet - Page 55

• Manufacturer Part Number: ez80l92
• Description: Ez80acclaim Flash Microcontrollers
• Manufacturer: ZiLOG Semiconductor

PS013014-0107
Memory Chip Select Priority
A lower-numbered Chip Select is given priority over a higher-numbered Chip Select. For
example, if the address space of Chip Select 0 overlaps the Chip Select 1 address space,
Chip Select 0 is active.
RESET States
On RESET, Chip Select 0 is active for all addresses, as its Lower Bound register resets to
00h
Upper Bound registers reset to
Memory Chip Select Example
The use of Memory Chip Selects is illustrated in
values are listed in
configured for memory addresses. Also, CS1 overlaps with CS0. As CS0 has the higher
than CS1, CS1 is not active for much of its defined address space.
CS0_LBR = CS1_LBR = 00h
and its Upper Bound register resets to
CS2_UBR = CFh
CS3_UBR = FFh
CS1_UBR = 9Fh
CS0_UBR = 7Fh
CS3_LBR = D0h
CS2_LBR = A0h
Table
Figure 4. Memory Chip Select Example
13. In this example, all 4 Chip Selects are enabled and
00h
3 MB Address Space
3 MB Address Space
2 MB Address Space
8 MB Address Space
.
CS3 Active
CS2 Active
CS1 Active
CS0 Active
FFh
. All of the other Chip Select Lower and
Figure
4. The associated control register
Memory
Location
FFFFFFh
D00000h
CFFFFFh
A00000h
9FFFFFh
800000h
7FFFFFh
000000h
Chip Selects and Wait States
Product Specification
eZ80L92 MCU
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