s3c72m9 Samsung Semiconductor, Inc., s3c72m9 Datasheet - Page 105

• Manufacturer Part Number: s3c72m9
• Description: The S3c72m5/s3c72m7/s3c72m9 Single-chip Cmos Microcontroller Has Been Designed For High Performance Using Samsung S
• Manufacturer: Samsung Semiconductor, Inc.

S3C72M5/C72M7/C72M9/P72M9 (Preliminary Spec)
SAM47 INSTRUCTION SET
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SAM47 INSTRUCTION SET
OVERVIEW
The SAM47 instruction set includes 1-bit, 4-bit, and 8-bit instructions for data manipulation, logical and arithmetic
operations, program control, and CPU control. I/O instructions for peripheral hardware devices are flexible and easy
to use. Symbolic hardware names can be substituted as the instruction operand in place of the actual address.
Other important features of the SAM47 instruction set include:
— 1-byte referencing of long instructions (REF instruction)
— Redundant instruction reduction (string effect)
— Skip feature for ADC and SBC instructions
Instruction operands conform to the operand format defined for each instruction. Several instructions have multiple
operand formats.
Predefined values or labels can be used as instruction operands when addressing immediate data. Many of the
symbols for specific registers and flags may also be substituted as labels for operations such DA, mema, memb, b,
and so on. Using instruction labels can greatly simplify program writing and debugging tasks.
INSTRUCTION SET FEATURES
In this section, the following SAM47 instruction set features are described in detail:
— Instruction reference area
— Instruction redundancy reduction
— Flexible bit manipulation
— ADC and SBC instruction skip condition
Instruction Reference Area
Using the 1-byte REF (REFerence) instruction, you can reference instructions stored in addresses 0020H–007FH of
program memory (the REF instruction look-up table). The location referenced by REF may contain either two 1-byte
instructions or a single 2-byte instruction. The starting address of the instruction being referenced must always be an
even number.
3-byte instructions such as JP or CALL may also be referenced using REF. To reference these 3-byte instructions,
the 2-byte pseudo commands TJP and TCALL must be written to the reference area instead of the normal JP or
CALL instruction.
The PC is not incremented when a REF instruction is executed. After it executes, the program's instruction ex-
ecution sequence resumes at the address immediately following the REF instruction. By using REF instructions to
execute instructions larger than one byte, as well as branches and subroutines, you can reduce the total number of
program steps. To summarize, the REF instruction can be used in three ways:
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