st72324bk STMicroelectronics, st72324bk Datasheet - Page 58

• Manufacturer Part Number: st72324bk
• Description: 3 V/5 V Range 8-bit Mcu With 4/8 Kbyte Rom, 10-bit Adc, Four Timers And Spi
• Manufacturer: STMicroelectronics

On-chip peripherals
Note:
9.1.5
58/167
Exact timeout duration (t
Where:
t
t
t
CNT = Value of T[5:0] bits in the WDGCR register (6 bits)
MSB and LSB are values shown in
TB[1:0] bits in the MCCSR register.
Table 27.
To calculate the minimum Watchdog timeout (t
If
else
To calculate the maximum Watchdog timeout (t
If
else
In the above formulas, division results must be rounded down to the next integer value.
Example: with 2 ms timeout selected in the MCCSR register:
Table 28.
Low- power modes
The low-power modes are shown in
min0
max0
OSC2
CNT
CNT
Value of T[5:0] bits in WDGCR
(MCCSR Reg.)
= (LSB + 128) x 64 x t
t min0
= 16384 x t
t max
= 125ns if f
TB1 bit
≤
<
0
0
1
1
MSB
------------ -
MSB
------------ -
register (hex.)
4
4
+
=
Time base selection
t
min
t max0
16384
3F
then
00
then
OSC2
OSC2
and t
+
×
t max
⎛
⎝
t min
(MCCSR Reg.)
=8 MHz
16384
CNT
max
TB0 bit
=
OSC2
=
values for a time base of 2 ms
–
0
1
0
1
×
t max0
min
t min0
4CNT
--------------- -
⎛
⎝
MSB
CNT
and t
Min. watchdog timeout (ms)
Table
+
+
Table
–
⎞
⎠
16384 CNT t osc2
16384 CNT t osc2
+
4CNT
--------------- -
MSB
max
Selected MCCSR time base
(
192
27, that depend on the time base selected by the
29.
×
)
×
+
1.496
⎞
⎠
t
128
min
LSB
min
max
+
(
):
192
×
×
10 ms
25 ms
):
)
2 ms
4 ms
×
+
64
LSB
×
4CNT
--------------- -
MSB
) 64
×
Max. watchdog timeout (ms)
×
4CNT
--------------- -
MSB
ST72323 ST72323L
MSB
20
49
128.552
4
8
2.048
t
max
×
t osc2
LSB
59
53
35
54