EZ80F91MCU Datasheet, PDF (131/396 Pages) Zilog, Inc. – eZ80Acclaim-TM Flash Microcontrollers

eZ80F91 MCU
Product Specification
112
Flash Address Upper Byte Register
The FLASH_ADDR_U register defines the upper 6 bits of the Flash memory
address space. Changing the value of FLASH_ADDR_U allows on-chip 256 KB
Flash memory to be mapped to any location within the 16 MB linear address
space of the eZ80F91 device. If on-chip Flash memory is enabled, the Flash
address assumes priority over any external Chip Selects. The external Chip
Select signals are not asserted if the corresponding Flash address is enabled.
Internal Flash memory does not hold priority over internal SRAM. See Table 36.
Table 36. Flash Address Upper Byte Register
(FLASH_ADDR_U = 00F7h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R/W R/W R/W R/W R/W R/W R
R
Note: R/W = Read/Write; R = Read Only.
Bit
Position
Value Description
[7:2]
00h–
FLASH_ADDR_U FCh
These bits define the upper byte of the Flash address. When
on-chip Flash is enabled, the Flash address space begins at
address {FLASH_ADDR_U, 00b, 0000h}. On-chip Flash has
priority over all external Chip Selects.
[1:0]
00 Reserved (enforces alignment on a 256KB boundary).
PS019209-0504
PRELIMINARY
Flash Memory