HD6432621 Hitachi, HD6432621 Datasheet - Page 71

• Manufacturer Part Number: HD6432621
• Description: (HD64F262x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

Instruction Set: All instructions and addressing modes can be used. Only the lower 16 bits of
effective addresses (EA) are valid.
Exception Vector Table and Memory Indirect Branch Addresses: In normal mode the top area
starting at H'0000 is allocated to the exception vector table. One branch address is stored per 16
bits (figure 2-2). The exception vector table differs depending on the microcontroller. For details
of the exception vector table, see section 4, Exception Handling.
The memory indirect addressing mode (@@aa:8) employed in the JMP and JSR instructions uses
an 8-bit absolute address included in the instruction code to specify a memory operand that
contains a branch address. In normal mode the operand is a 16-bit word operand, providing a 16-
bit branch address. Branch addresses can be stored in the top area from H'0000 to H'00FF. Note
that this area is also used for the exception vector table.
Note: * Not available in the H8S/2626 Series or H8S/2623 Series.
Figure 2-2 Exception Vector Table (Normal Mode)
H'0000
H'0001
H'0002
H'0003
H'0004
H'0005
H'0006
H'0007
H'0008
H'0009
H'000A
H'000B
Manual reset exception vector *
(Reserved for system use)
Reset exception vector
Exception vector 1
Exception vector 2
Exception
vector table
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