4-5 Time Base Operation

4-5-1 Overview

The clock source for the time base timer can be set to fosc or fx. Also, the interrupt
period for time base timer (TBIRQ) can be set to 1/27, 1/28, 1/29, 1/210, or 1/213 of the
clock source.

4-5-2 Operation

Time Base Function
Settings for the time base function are listed below.
(1) Use the TM5CK0 flag of the timer 5 mode register (TM5MD) to select fosc or fx as
the clock source.
(2) Use the TM5IR2 to 0 flags of the TM5MD register to select the time base timer
interrupt source.
(3) When the selected time interval passes, the interrupt request flag of the time base
interrupt control register (TBICR) is set.
Table 4-5-1 Base Time Settings
Chapter 4 Timer Functions
77
TM5IR2 to 0
Clock Source
fosc 20MHz
8.38MHz
32.768kHz
6.4µs
15.2µs
3.9ms
12.8µs
30.5µs
7.8ms
25.6µs
61.0µs
15.6ms
51.2µs
122.0µs
31.2ms
409.6µs
000 001 010 011 1XX
1
271
281
291
210 1
213
976.4µs
250ms
fx
Time base operation cannot be halted.
Time Base Operation