844
Bits 1 and 0—Frequency Multiplication Factor (STC1, STC0): The STC bits specify the
frequency multiplication factor of the PLL circuit.
Bit 1
Bit 0
STC1
STC0
Description
0
0
×
1
(Initial value)
1
×
2
1
0
×
4
1
Setting prohibited
Note:
A system clock frequency multiplied by the multiplication factor (STC1 and STC0) should
not exceed the maximum operating frequency defined in section 25 Electrical
Characteristics.
23.3
Oscillator
Clock pulses can be supplied by connecting a crystal resonator, or by input of an external clock.
23.3.1
Connecting a Crystal Resonator
Circuit Configuration: A crystal resonator can be connected as shown in the example in figure
23-2. Select the damping resistance R
d
according to table 23-2. An AT-cut parallel-resonance
crystal should be used.
EXTAL
XTAL
R
d
C
L2
C
L1
C
L1
= C
L2
= 10 to 22pF
Figure 23-2 Connection of Crystal Resonator (Example)
Table 23-2 Damping Resistance Value
Frequency (MHz) 2
4
8
12
16
20
25
R
d
(
Ω
)
1 k
500
200
0
0
0
0
Crystal Resonator: Figure 23-3 shows the equivalent circuit of the crystal resonator. Use a
crystal resonator that has the characteristics shown in table 23-3.
Содержание H8S/2631
Страница 28: ...xviii Appendix G Package Dimensions 1154 ...
Страница 341: ...316 Transfer SAR or DAR DAR or SAR Block area First block Nth block Figure 9 8 Memory Mapping in Block Transfer Mode ...
Страница 918: ...905 ø DREQ0 DREQ1 tDRQS tDRQH Figure 25 19 DMAC DREQ Input Timing ...
Страница 955: ...943 A 2 Instruction Codes Table A 2 shows the instruction codes ...