CHAPTER 6 16-BIT TIMER/EVENT COUNTERS 00 AND 01
User’s Manual U16899EJ2V0UD
151
Figure 6-13. Format of Prescaler Mode Register 01 (PRM01)
Address: FFB7H After reset: 00H R/W
Symbol
7 6 5 4 3 2 1 0
PRM01 ES111 ES110 ES011 ES010
0
0 PRM011
PRM010
ES111
ES110
TI011 pin valid edge selection
0 0
Falling
edge
0 1
Rising
edge
1 0
Setting
prohibited
1
1
Both falling and rising edges
ES011
ES010
TI001 pin valid edge selection
0 0
Falling
edge
0 1
Rising
edge
1 0
Setting
prohibited
1
1
Both falling and rising edges
PRM011
PRM010
Count clock selection
Note 1
0 0
f
X
(10 MHz)
0 1
f
X
/2
4
(625 kHz)
1 0
f
X
/2
6
(156.25 kHz)
1 1
TI001
valid
edge
Note 2
Notes 1. Be sure to set the count clock so that the following condition is satisfied.
•
V
DD
= 4.0 to 5.5 V: Count clock
≤
10 MHz
•
V
DD
= 3.3 to 4.0 V: Count clock
≤
8.38 MHz
•
V
DD
= 2.7 to 3.3 V: Count clock
≤
5 MHz
•
V
DD
= 2.5 to 2.7 V: Count clock
≤
2.5 MHz
2. The external clock requires a pulse longer than two cycles of the internal count clock (f
X
).