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CHAPTER 4 INSTRUCTION SET
4.1.4 Description of “clock” column
The number of clock cycles during instruction execution is outlined as follows.
1 instruction clock cycle is 1 CPU clock cycle (f
CPU
) selected by the processor clock control register (PCC).
(1) Classification of “clock” column
The number of instruction clocks differs in the following two cases.
<1> When the internal high-speed RAM area is accessed, or in the instruction with no data access
<2> When an area except the internal high-speed RAM area is accessed
(2) When “n” or “m” is written in “clock” column
n indicates the number of waits when external memory expansion area is read.
m indicates the number of waits when external memory expansion area is written to.
(3) Number of clocks if program is stored in external ROM
<1> When no wait cycle is inserted
The number of clocks is the same as when the program is stored in the internal ROM area.
<2> When wait cycle is inserted
The number of clocks differs depending on the product. There are the following three product groups
classified according to the number of clocks.
With
μ
PD78002, 78002Y, 78014, 78014Y, 78014H, 78018F, 78018FY, 78P0914 Subseries
The number of clocks increases by
“the number of bytes
×
number of wait cycles
×
2”
, as
compared with when the program is stored in the internal ROM area.
μ
PD78054, 78054Y, 78058F, 78058FY, 78075B, 78075BY, 78078, 78078Y, 78098, 78098B,
780018Y, 780024, 780024Y, 780034, 780034Y, 780058, 780058Y, 780308, 780308Y, 780924,
780964 Subseries
The number of clocks increases by
“the number of bytes
×
number of wait cycles”
, as compared
with when the program is stored in the internal ROM area.
μ
PD78070A, 78070AY
The
μ
PD78070A and 78070AY do not incorporate an internal ROM area.
The number of clocks depends on the instruction (See
4.1.5 Operation list (4)
).
The number of clocks during instruction execution differs in the product. These are divided into the following
four groups.
μ
PD78002, 78002Y, 78014, 78014Y, 78014H, 78018F, 78018FY Subseries and
μ
PD780001, 78P0914
μ
PD78044F, 78044H, 78064, 78064Y, 78064B, 780208, 780228 Subseries
μ
PD78054, 78054Y, 78058F, 78058FY, 78075B, 78075BY, 78078, 78078Y, 78083, 78098, 78098B,
780018Y, 780024, 780024Y, 780034, 780034Y, 780058, 780058Y, 780308, 780308Y, 780924, 780964
Subseries
μ
PD78070A, 78070AY
The operation list for each product is shown below.