Zilog EZ80F91GA - Manual (Page 56)

ZGATE Memory Layout UM024502-1012
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ZGATE Embedded Security Development Kit
User Manual
ZGATE Memory Layout
ZGATE imposes the following restrictions on the memory layout of the system:
•
ZGATE requires exclusive access to the first 64 KB of eZ80F91 internal Flash
– Customer applications that use internal Flash must use a starting address of
0x010000
– eZ80F91 Internal Flash must be enabled and mapped to address 0x000000
•
ZGATE requires exclusive access to all 8 KB of eZ80F91 general-purpose RAM
– eZ80F91 EMAC RAM must be mapped to 0xFFC000
•
External Flash must be connected to CS0
– A ZTP application targeting a Flash or Copy to RAM build configuration must use
a start address of
0x100000
•
External RAM must be connected to CS1 (if the ZTP application targets a RAM
build)
– A ZTP application using a RAM build configuration must use a starting address of
0x040000

During system startup, ZGATE will look for ZTP applications to launch at specific
addresses in the memory map, and will proceed in the following sequence:
•
Look for an application at address 0x040000 . If an application is found at this
address, ZGATE will start the ZTP application. If an application is not found, then:
•
Look for a ZTP application at address 0x010000 . If an application is found at this
address, ZGATE will start the ZTP application. If an application is not found, then:
•
Look for a ZTP application at address 0x100000 . If an application is found at this
address, ZGATE will start the ZTP application. If an application is not found, then:
•
Place the eZ80F91 into Sleep Mode using an eZ80 SLP instruction.

ZGATE applications should use the ZTGT files included in the ZGATE_Demo folder.
These target files have been created with the appropriate settings for the ZGATE Embed-
ded Security Development Kit. Similarly, the ZDS II
ZGATE_Demo_ZGATE000100ZCOG

.zdsproj project file contains the appropriate memory settings for the ZGATE Embed-
ded Security Development Kit.
Table 3 defines the range of addresses used in eZ80F91 MCU memory for ZGATE.