Fujitsu mb91192 Manuale Utente
190
CHAPTER 10 Timer
10.3
Register of 16-bit Timer (Timer 0 to 4)
Register configuration/functions of 16-bit timer (timer 0 to 4) is shown.
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Timer Control Register L (TxCRL)
Figure 10.3-1 Timer control register L (TxCRL)
[bit7 to 5]:
It is an unused bit.
[bit4]:LREQ
It is timer data load request bit.
Always read "0" at reading.
[bit3]:LFLG
It is timer data load complete flag bit.
[bit2]:TC1
[bit1]:TC0
There are clock source selection bit. Timer 0 to 4 is as follow.
7 6 5 4 3 2 1 0
---0 0000
B
Initial value
bit
Access
LREQ
LFLG
TC1
TC0
TSTR
R/W
R/W
R/W
R/W
R
0 None
1
Load request is performed timer data to compare latch and output
compare data to output latch.
compare data to output latch.
0
Timer data load complete.
1
Timer data load does not complete.
Table 10.3-1 Timer 0 to 3
TC1 TC0
Selection
Clock
Clock cycle time
(fch:@20MHz)
0 0
Internal clock
2
4
/fch (FRC3)
0.8
µs
0 1
2
6
/fch (FRC5)
3.2
µs
1 0
2
8
/fch (FRC7)
12.8
µs
1 1
2
10
/fch (FRC9)
51.2
µs