Section 10 Clock Pulse Generator (CPG)
Rev. 5.00 May 29, 2006 page 307 of 698
REJ09B0146-0500
Table 10.2
Clock Operating Modes
Pin Values
Clock I/O
Mode MD2 MD1 MD0
Source
Output
PLL2
On/Off
PLL1
On/Off
Divider 1
Input
Divider 2
Input
CKIO
Frequency
0
0
0
0
EXTAL
CKIO
On,
multiplication ratio: 1
On
PLL1 output
PLL1
(EXTAL)
1
0
0
1
EXTAL
CKIO
On,
multiplication ratio: 4
On
PLL1 output
PLL1
(EXTAL)
×
4
2
0
1
0
Crystal
oscillator
CKIO
On,
multiplication ratio: 4
On
PLL1 output
PLL1
(Crystal)
×
4
7
1
1
1
CKIO
—
Off
On
PLL1 output
PLL1
(CKIO)
—
Other than the
above
Reserved (setting disabled)
Mode 0: An external clock is input from the EXTAL pin and undergoes waveform shaping by
PLL circuit 2 before being supplied inside this LSI. The frequency ratio between EXTAL input
clock and CKIO output clock is 1:1. An input clock frequency of 25 MHz to 66.67 MHz can be
used, and the CKIO frequency range is 25 MHz to 66.67 MHz.
Mode 1: An external clock is input from the EXTAL pin and its frequency is multiplied by 4 by
PLL circuit 2 before being supplied inside this LSI, allowing a low-frequency external clock to be
used. The frequency ratio between EXTAL input clock and CKIO output clock is 1:4. An input
clock frequency of 6.25 MHz to 16.67 MHz can be used, and the CKIO frequency range is 25
MHz to 66.67 MHz.
Mode 2: The on-chip crystal oscillator operates, with the oscillation frequency being multiplied
by 4 by PLL circuit 2 before being supplied inside this LSI, allowing a low crystal frequency to be
used. The frequency ratio between crystal oscillation and CKIO output clock is 1:4. A crystal
oscillation frequency of 6.25 MHz to 16.67 MHz can be used, and the CKIO frequency range is 25
MHz to 66.67 MHz.
Mode 7: In this mode, the CKIO pin is an input, an external clock is input to this pin, and
undergoes waveform shaping, and also frequency multiplication according to the setting, by PLL
circuit 1 before being supplied to this LSI. In modes 0 to 2, the system clock is generated from the
output of this LSI’s CKIO pin. Consequently, if a large number of Ics are operating synchronized
with the clock, the CKIO pin load will be large. This mode, however, assumes a comparatively
large-scale system. If a large number of ICs are operating on the clock cycle, a clock generator
with a number of low-skew clock outputs can be provided, so that the ICs can operate
synchronously by distributing the clocks to each one.
Содержание SH7706 Series
Страница 8: ...Rev 5 00 May 29 2006 page viii of xlviii ...
Страница 160: ...Section 5 Cache Rev 5 00 May 29 2006 page 112 of 698 REJ09B0146 0500 ...
Страница 370: ...Section 11 Watchdog Timer WDT Rev 5 00 May 29 2006 page 322 of 698 REJ09B0146 0500 ...
Страница 532: ...Section 16 Serial Communication Interface with FIFO SCIF Rev 5 00 May 29 2006 page 484 of 698 REJ09B0146 0500 ...
Страница 554: ...Section 17 Pin Function Controller PFC Rev 5 00 May 29 2006 page 506 of 698 REJ09B0146 0500 ...
Страница 576: ...Section 18 I O Ports Rev 5 00 May 29 2006 page 528 of 698 REJ09B0146 0500 ...
Страница 614: ...Section 21 User Debugging Interface H UDI Rev 5 00 May 29 2006 page 566 of 698 REJ09B0146 0500 ...
Страница 746: ...Index Rev 5 00 May 29 2006 page 698 of 698 REJ09B0146 0500 ...
Страница 749: ...SH7706 Group Hardware Manual ...