Z86D99 ZILOG [Zilog, Inc.], Z86D99 Datasheet - Page 19

• Manufacturer Part Number: Z86D99
• Description: Low-Voltage Micro controllers with ADC
• Manufacturer: ZILOG [Zilog, Inc.]

PS003807-1002
Figure 5. Program Memory Map
Z8 Standard Register File (Bank 0)
Bank 0 of the Z8 expanded register file architecture is known as the standard reg-
ister file of the Z8. As shown in Figure 6, the Z8 standard register file consists of
16 groups of sixteen 8-bit registers known as Working Register (WR) groups.
Working Register Group F contains various control and status registers. The lower
half of Working Register Group 0 consists of I/O port registers (R0 to R7), the
upper eight registers are available for use as general-purpose RAM registers.
Working Register Group 1 through Group E of the standard register file are avail-
able to be used as general-purpose RAM registers. The user can use 233 bytes of
general-purpose RAM registers in the standard Z8 register file (Bank 0).
Location (Hex)
FFFF
FF00
3FFF/7FFF
(ROM)/(OTP)
000C
000B
000A
0009
0008
0007
0006
0005
0004
0003
0002
0001
0000
Location of the first byte of the initial instruction executed after
P
R
E
L
I
M
Z86D990/Z86D991 OTP and Z86L99X ROM
IRQ
IRQ
IRQ
IRQ
IRQ
IRQ
Executable RAM
IRQ
IRQ
IRQ
IRQ
IRQ
IRQ
Not Implemented
I
Low-Voltage Microcontrollers with ADC
PROGRAM
MEMORY
256 bytes
5
4
3
2
1
0
5
4
3
2
1
0
N
RESET
(upper byte)
(upper byte)
(upper byte)
(upper byte)
(upper byte)
(upper byte)
(lower byte)
(lower byte)
(lower byte)
(lower byte)
(lower byte)
(lower byte)
A
R
Y
12