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CHAPTER 5 CPU ARCHITECTURE
5.1.1 Internal program memory space
The internal program memory space stores programs and table data. This space is usually addressed by the
program counter (PC).
Each model in the
μ
PD78018F, 78018FY subseries is provided with the following internal ROM (or PROM):
Table 5-1. Internal ROM Capacity
Part Number
Capacity
Structure
μ
PD78011F, 78011FY
Mask ROM
8192
×
8 bits (0000H-1FFFH)
μ
PD78012F, 78012FY
16384
×
8 bits (0000H-3FFFH)
μ
PD78013F, 78013FY
24576
×
8 bits (0000H-5FFFH)
μ
PD78014F, 78014FY
32768
×
8 bits (0000H-7FFFH)
μ
PD78015F, 78015FY
40960
×
8 bits (0000H-9FFFH)
μ
PD78016F, 78016FY
49152
×
8 bits (0000H-BFFFH)
μ
PD78018F, 78018FY
61440
×
8 bits (0000H-EFFFH)
μ
PD78P018F, 78P018FY
PROM
61440
×
8 bits (0000H-EFFFH)
The following areas are allocated to the internal program memory space:
(1) Vector table area
A 64-byte area of addresses 0000H-003FH is reserved as a vector table area. This area stores program start
addresses to which execution branches when the RESET signal is input or when an interrupt request is
generated. Of a 16-bit program start address, the low-order 8 bits are stored in an even address, and the
high-order 8 bits are stored in an odd address.
Table 5-2. Vector Table
Vector Table Address
Interrupt Source
Vector Table Address
Interrupt Source
0000H
RESET input
0010H
INTCSI1
0004H
INTWDT
0012H
INTTM3
0006H
INTP0
0014H
INTTM0
0008H
INTP1
0016H
INTTM1
000AH
INTP2
0018H
INTTM2
000CH
INTP3
001AH
INTAD
000EH
INTCSI0
003EH
BRK instruction
(2) CALLT instruction table area
In a 64-byte area of addresses 0040H-007FH, the subroutine entry address of a 1-byte call instruction (CALLT)
can be stored.
(3) CALLF instruction entry area
From an area of addresses 0800H-0FFFH, a subroutine can be directly called by using a 2-byte call instruction
(CALLF).