Z87233 Datasheet, PDF (18/71 Pages) Zilog, Inc. – CMOS Z8-R MCU Consumer Controller Processor

See Figure 7.
Z87233
CMOS Z8“ MCU Consumer Controller Processor
12
65537
8192
8191
Location of first Byte
of Instruction Executed
after RESET
12
11
10
9
8
Interrupt ⁷
Vector
(Lower Byte)
6
5
Interrupt ⁴
Vector
(Upper Byte)
3
2
1
0
Reserved
On-Chip
ROM
IRQ5
IRQ5
IRQ4
IRQ4
IRQ3
IRQ3
IRQ2
IRQ2
IRQ1
IRQ1
IRQ0
IRQ0
Figure 7.Program Memory Map
ROM Protect. ROM PROTECT provides an additional security function. When the
ROM PROTECT option bit is selected, and executing out of Internal Program
Memory, instructions LDC, LDCI, LDE, and LDEI can read Internal Program Mem-
ory.
RAM Protect. The upper portion of the RAM’s address spaces 80h to EFh (exclud-
ing the control registers) can be protected from writing. The RAM Protect option
bit can be selected when the device is programmed. After the mask option is
selected, the user activates this feature from the internal ROM code to turn off/on
the RAM Protect by loading either a 0 or a 1 into the IMR register, bit D6. A 1 in bit
D6 enables the RAM Protect option.
PS022701-0104