UPD78F0988AGC-8BS Renesas Electronics America, UPD78F0988AGC-8BS Datasheet - Page 101

• Manufacturer Part Number: UPD78F0988AGC-8BS
• Manufacturer: Renesas Electronics America

Specifications of UPD78F0988AGC-8BS

• Lead Free Status / Rohs Status: Supplier Unconfirmed

5.3 Register Controlling Clock Generator
between the CPU clock (f
The clock generator is controlled by the processor clock control register (PCC). This register selects the CPU clock.
PCC is set by a 1-bit or 8-bit memory manipulation instruction.
RESET input sets this register to 04H.
Caution Be sure to clear bits 3 to 7 to 0.
Remark f
The fastest instruction of the PD780988 Subseries is executed in two CPU clocks. Therefore, the relationship
Symbol
PCC
Table 5-2. Relationship Between CPU Clock and Minimum Instruction Execution Time
0
Note Expanded-specification products only.
Remark f
7
X
: System clock oscillation frequency
f
f
f
f
f
X
X
X
X
X
/2
/2
/2
/2
2
3
4
CPU Clock (f
6
0
X
: System clock oscillation frequency
CPU
5
Figure 5-2. Format of Processor Clock Control Register
0
) and the minimum instruction execution time is as shown in Table 5-2.
CPU
4
0
)
3
0
CHAPTER 5 CLOCK GENERATOR
0.166 s
0.33 s
0.66 s
1.3 s
2.6 s
User’s Manual U13029EJ7V1UD
PCC2 PCC1 PCC0
2
At f
X
Minimum Instruction Execution Time: 2/f
1
= 12 MHz
0
Note
PCC2
Other than above
0
0
0
0
1
Address
FFFBH
PCC1 PCC0
0
0
1
1
0
0.238 s
0.48 s
0.96 s
1.9 s
3.8 s
0
1
0
1
0
After reset
At f
04H
X
f
f
f
f
f
Setting prohibited
X
X
X
X
X
= 8.38 MHz
/2
/2
/2
/2
Selects CPU cIock (f
2
3
4
CPU
R/W
R/W
CPU
)
99