NEC PD754144, PD754244 11.2 Instruction Set and Operation

CHAPTER 11 INSTRUCTION SET
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User’s Manual U10676EJ3V0UM
11.1.5 Skip instruction and number of machine cycles required for skipping
The instruction set of the µ PD754244 configures a program where instructions may be or may not be skipped if
a given condition is satisfied.
If a skip condition is satisfied when a skip instruction is executed, the instruction next to the skip instruction is
skipped and the instruction after next is executed.
When a skip occurs, the number of machine cycles required for skipping is:
(a) If the instruction that follows the skip instruction (i.e., the instruction to be skipped) is a 3-byte
instruction (BR !addr, BRA !addr1, CALL !addr, or CALLA !addr1 instruction): 2 machine cycles
(b) Instruction other than (a): 1 machine cycle
11.2 Instruction Set and Operation
(1) Operand representation and description
Describe an operand in the operand field of each instruction according to the operand description method of
the instruction (for details, refer to RA75X Assembler Package Language User’s Manual. If two or more
operands are shown, select one of them. Uppercase letters, +, and - are keywords and must be described
as is.
The symbols of register flags can be described as labels, instead of mem, fmem, pmem, and bit. (However,
the number of labels described for fmem and pmem are limited. For details, refer to Table 3-1 Addressing
Modes and Figure 3-7
µ PD754244 I/O Map).