tmp88ch40img TOSHIBA Semiconductor CORPORATION, tmp88ch40img Datasheet - Page 17

• Manufacturer Part Number: tmp88ch40img
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

2.1.4 System Clock Control Circuit
2.1.4.1
2.1.4.2
cuit.
The System Clock Control Circuit consists of a clock generator, timing generator, and standby control cir-
clocks supplied to the CPU core and peripheral hardware units.
and XOUT pins. Or a clock generated by an external oscillator can also be used. In this case, enter the
external clock from the XIN pin and leave the XOUT pin open. The TMP88CH40IMG does not support
the CR network that produces a time constant.
the CPU core and peripheral hardware units. The Timing Generator has the following functions:
XOUT
Clock Generator
Timing Generator
XIN
The Clock Generator generates the fundamental clock which serves as the reference for the system
The high-frequency clock (frequency fc) can be obtained easily by connecting a resonator to the XIN
Adjusting the oscillation frequency
Note: Although no hardware functions are provided that allow the fundamental clock to be monitored directly
The Timing Generator generates various system clocks from the fundamental clock that are supplied to
from the outside, the oscillation frequency can be adjusted by forwarding the pulse of a fixed frequency
(e.g., clock output) to a port and monitoring it in a program while interrupts and the watchdog timer are
disabled. For systems that require adjusting the oscillation frequency, an adjustment program must be
created beforehand.
Figure 2-3 Example for Connecting a Resonator
Figure 2-2 System Clock Control Circuit
(a) Using a crystal or
High-frequency
clock oscillator
XIN
generator
ceramic resonator
Clock
circuit
High-frequency Clock
XOUT
Timing generator control register
fc
Page 9
Timing generator
System clocks
(b) Using an external
XIN
TBTCR
oscillator
00036H
(Open)
XOUT
Standby control circuit
00039H
System control register
SYSCR2
TMP88CH40IMG