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CHAPTER 3 CPU ARCHITECTURE
User
’
s Manual U14701EJ3V0UD
3.1.1 Internal program memory space
The internal program memory space contains the program and table data. Normally, it is addressed with the
program counter (PC).
The
μ
PD780318, 780328, and 780338 Subseries products incorporate an internal ROM (or flash memory), as listed
below.
Table 3-1. Internal Memory Capacity
Part Number
Structure
Capacity
μ
PD780316, 780326, 780336
Mask ROM
49,152
×
8 bits (0000H to BFFFH)
μ
PD780318, 780328, 780338
61,440
×
8 bits (0000H to EFFFH)
μ
PD78F0338
Flash memory
The internal program memory space is divided into the following three areas.
(1) Vector table area
The 64-byte area 0000H to 003FH is reserved as a vector table area. The RESET input and program start
addresses for branch upon generation of each interrupt request are stored in the vector table area. Of the 16-
bit address, lower 8 bits are stored at even addresses and higher 8 bits are stored at odd addresses.
Table 3-2. Vector Table
Vector Table Address
Interrupt Source
Vector Table Address
Interrupt Source
0000H
RESET input
001AH
INTCSI1
0004H
INTWDT
001CH
INTCSI3
0006H
INTP0
001EH
INTWTNI0
0008H
INTP1
0020H
INTTM00
000AH
INTP2
0022H
INTTM01
000CH
INTP3
0024H
INTTM4
000EH
INTP4
0026H
INTTM50
0010H
INTP5
0028H
INTTM51
0012H
INTKR
002AH
INTTM52
0014H
INTSER0
002CH
INTAD0
0016H
INTSR0
002EH
INTWTN0
0018H
INTST0
003EH
BRK
(2) CALLT instruction table area
The 64-byte area 0040H to 007FH can store the subroutine entry address of a 1-byte call instruction (CALLT).
(3) CALLF instruction entry area
The area 0800H to 0FFFH can perform a direct subroutine call with a 2-byte call instruction (CALLF).