tmp88cu74 TOSHIBA Semiconductor CORPORATION, tmp88cu74 Datasheet - Page 53

• Manufacturer Part Number: tmp88cu74
• Description: Cmos 8-bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

2.3
Time Base Timer (TBT)
provides a time base timer interrupt (INTTBT).
timing generator) after the time base timer has been enabled. The divider is not cleared by the
program; therefore, only the first interrupt may be generated ahead of the set interrupt period
(Figure 2.3.1 (b)).
interrupt frequency must not be changed with the disable from the enable state). Both
frequency selection and enabling can be performed simultaneously.
The time base timer generates time base for key scanning, dynamic displaying, etc. It also
An INTTBT is generated on the first rising edge of source clock (the divider output of the
The interrupt frequency (TBTCK) must be selected with the time base timer disabled (the
fc/2
fc/2
fc/2
fc/2
fc/2
fc/2
fc/2
fc/2
Example: Sets the time base timer frequency to fc/2
23
21
16
14
13
12
11
9
, fc/2
Source clock
TBTEN
INTTBT
, fc/2
, fc/2
, fc/2
, fc/2
, fc/2
, fc/2
, fc/2
10
24
22
17
15
14
13
12
or fs/2
or fs/2
or fs/2
or fs/2
or fs/2
or fs/2
or fs/2
or fs/2
LD
SET
Figure 2.3.1 Time Base Timer
15
13
8
6
5
4
3
Enable TBT
(b) Time base timer interrupt
Time base timer control register
TBTCK
(a) Configuration
A
B
C
D
E
F
G
H
(TBTCR), 00001010B
(EIRL). 6
3
88CU74-53
MPX
S
Interrupt period
TBTCR
Y
Source
clock
TBTEN
16
[Hz] and enables an INTTBT interrupt.
Rising edge
detector
INTTBT interrupt request
TMP88CU74
2007-10-19
2003-02-17