NEC PD754144 User Manual
Page 241
CHAPTER 11 INSTRUCTION SET
241
User’s Manual U10676EJ3V0UM
(4) Explanation of machine cycle field
S indicates the number of machine cycles required for an instruction with skip to execute the skip operation.
The value of S varies as follows.
•
When skip is executed .............................................................................. S = 0
•
When 1- or 2-byte instruction is skipped ................................................. S = 1
•
When 3-byte instruction
Note
is skipped .................................................... S = 2
Note
3-byte instructions: BR !addr, BRA !addr1, CALL !addr, CALLA !addr1
Caution
The GETI instruction is skipped in one machine cycle.
One machine cycle is equal to one cycle of CPU clock
Φ (= t
CY
), and four times can be set by PCC (refer to
Figure 6-15 Processor Clock Control Register Format).