HD64F2145 Datasheet, PDF (655/829 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

25.7 Clock Select Circuit
The clock select circuit selects the system clock that is used in this LSI.
A clock generated by an oscillator to which the EXTAL and XTAL pins are input is selected as a
system clock when returning from high-speed mode, medium-speed mode, sleep mode, reset state,
or standby mode.
A subclock input from the EXCL pin is selected as a system clock in subactive mode, subsleep
mode, or watch mode. At this time, modules such as the CPU, TMR_0, TMR_1, WDT_0,
WDT_1, ports, and interrupt controller and their functions operate depending on the øSUB. The
count clock and sampling clock for each timer are divided øSUB clocks.
25.8 Processing for X1 and X2 Pins
The X1 and X2 pins should be open as shown in figure 25.8.
X1
Open
X2
Open
Figure 25.8 Processing for X1 and X2 Pins
Rev. 2.0, 08/02, page 615 of 788