Z8E520 Datasheet, PDF (18/43 Pages) Zilog, Inc. – 1.5 MBPS USB Device Controller

Z8E520/C520
1.5 MBPS USB Device Controller
FUNCTIONAL DESCRIPTION
Program Memory. The 16-bit program counter addresses
6 KB of program memory space at internal locations
(Figure 11).
Zilog
The first 14 bytes of program memory are reserved for the
rollover and interrupt vectors. These locations have six
16-bit vectors that correspond to the six available inter-
rupts.
ADDRESS
DECIMAL HEX
6143
17FF
ON-CHIP EPROM PROGRAM MEMORY
33
021
32
020
31
01F
AVAILABLE TO USER (AREA INTENDED
FOR FUTURE ADDITIONAL INTERRUPTS)
14
00E
13
00D
IRQ5
12
00C
IRQ5
LOCATION OF FIRST
BYTE OF INSTRUCTION
EXECUTED AFTER
RESET
11
00B
IRQ4
10
00A
IRQ4
9
009
IRQ3
8
008
IRQ3
7
007
IRQ2 INTERRUPT VECTOR (Lower Byte)
6
006
IRQ2 INTERRUPT VECTOR (Upper Byte)
5
005
IRQ1
4
004
IRQ1
3
003
2
002
IRQ0
IRQ0
1
001
PC ROLLOVER VECTOR (Lower Byte)
0
000
PC ROLLOVER VECTOR (Upper Byte)
Figure 11. Z8E520 Program Memory Map
18
PRELIMINARY
DS97KEY2005