HD6475328-CP10 HITACHI [Hitachi Semiconductor], HD6475328-CP10 Datasheet - Page 63

• Manufacturer Part Number: HD6475328-CP10
• Description: original Hitachi CMOS microcomputer unit (MCU)
• Manufacturer: HITACHI [Hitachi Semiconductor]

Table 3-6 Data Formats on the Stack
Data Type
Byte data
on stack
Word data
on stack
3.4 Instructions
3.4.1 Basic Instruction Formats
There are two basic CPU instruction formats: the general format and the special format.
General format: This format consists of an effective address (EA) field, an effective address
extension field, and an operation code (OP) field. The effective address is placed before the
operation code because this results in faster execution of the instruction.
• Effective address field:
• Effective address extension: Zero to two bytes containing a displacement value, immediate
• Operation code:
Effective address field
Data Format
Even address
Even address
Odd address
Odd address
One byte containing information used to calculate the effective
address of an operand.
data, or an absolute address. The size of the effective address
extension is specified in the effective address field.
Defines the operation to be carried out on the operand located at
the address calculated from the effective address information.
Some instructions (DADD, DSUB, MOVFPE, MOVTPE) have
an extended format in which the operand code is preceded by a
one-byte prefix code.
Effective address extension
44
MSB
MSB
Upper 8 bits
Lower 8 bits
Don’t-care
Operation code
LSB
LSB