HD404618 Datasheet, PDF (8/89 Pages) Hitachi Semiconductor – 4-Bit Single-Chip Microcomputer

HD404618 Series
Memory Map
ROM Memory Map
The ROM memory map is shown in figure 1, and the ROM is described below.
0
15
16
63
64
4095
4096
8191
8192
16383
Vector address
Zero-page subroutine
(64 words)
Pattern
(4096 words)
Program*
$0000
$000F
$0010
$003F
$0040
$0FFF
$1000
$1FFF
$2000
Not used
$3FFF
0
JMPL instruction
$0000
1
(jump to reset routine)
$0001
2
JMPL instruction
$0002
3
(jump to INT₀ routine)
$0003
4
JMPL instruction
$0004
5
(jump to INT₁ routine)
$0005
6
JMPL instruction
$0006
7
(jump to timer A routine)
$0007
8
JMPL instruction
$0008
9 ^{(jump to timer B routine)} $0009
10
JMPL instruction
$000A
11 ^{(jump to timer C routine)} $000B
12
JMPL instruction
$000C
13
(jump to serial routine)
$000D
14
$000E
15
$000F
Note: * HD404612: 2048 words
HD404614: 4096 words
HD404616: 6144 words
HD404618, HD4074618: 8192 words
Figure 1 ROM Memory Map
Vector Address Area ($0000–$000F): Reserved for JMPL instructions that branch to the start addresses
of the reset and interrupt routines. After an MCU reset or interrupt execution, the program starts from the
vector address.
Zero-Page Subroutine Area ($0000–$003F): Reserved for subroutines. The program branches to a
subroutine in this area in response to the CAL instruction.
Pattern Area ($0000–$0FFF): Contains ROM data that can be referenced with the P instruction.
Program Area ($0000–$07FF (HD404612), $0000–$0FFF (HD404614), $0000–$17FF (HD404616),
$0000–$1FFF (HD404618, HD4074618)): Used for program coding.
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