10 STOPWaTCh TiMeR
S1C63003/004/008/016 TeChniCal Manual
Seiko epson Corporation
10-3
(Rev. 1.1)
Direct LAP input (P01/P00)
Direct LAP internal signal
Capture renewal flag CRNWF
SWD[3:0] reading
SWD[7:4] reading
SWD[11:8] reading
Data holding
S1C63004/008/016
4.1 Timing for data holding and reading
Figure 10.
Stopwatch Timer Run/STOP and Reset
10.5
RUN/STOP control and reset of the stopwatch timer can be done by software.
Stopwatch timer Run/STOP
The stopwatch timer enters the RUN status when "1" is written to SWRUN, and the STOP status when "0" is
written. In the STOP status, the timer data is maintained until the next RUN status or resets timer. Also, when the
STOP status changes to the RUN status, the data that was maintained can be used for resuming the count. The
RUN/STOP operation of the stopwatch timer by writing to the SWRUN register is performed in synchronization
with the falling edge of the 1,024 Hz same as the prescaler input clock. The SWRUN register can be read, and in
this case it indicates the operating status of the stopwatch timer.
Figure 10.5.1 shows the operating timing when controlling the SWRUN register.
f
OSC1
/32 (1,024 Hz)
SWRUN writing
SWRUN register
Count clock
5.1 Operating timing when controlling SWRUN
Figure 10.
When the direct input function (explained in next section) is set, RUN/STOP control is done by an external key
input. In this case, SWRUN becomes read only register that indicates the operating status of the stopwatch timer
(S1C63004/008/016).
Stopwatch timer reset
The stopwatch timer is reset when "1" is written to SWRST. With this, the counter value is cleared to "000." Since
this resetting does not affect the capture buffer, data that has been held in the capture buffer is not cleared and is
maintained as is. When the stopwatch timer is reset in the RUN status, counting restarts from count "000." Also,
in the STOP status the reset data "000" is maintained until the next RUN.
Direct input Function and Key Mask
10.6
[S1C63004/008/016]
The S1C63004/008/016 stopwatch timer has a direct input function that can control the RUN/STOP and LAP opera-
tion of the stopwatch timer by external key input. This function is set by writing "1" to the EDIR register. When EDIR
is set to "0," only the software control is possible as explained in the previous section.
input port configuration
In the direct input function, the input ports P00 and P01 are used as the RUN/STOP and LAP input ports. The key
assignment can be selected using the SWDIR register.
6.1 RUN/STOP and LAP input ports
Table 10.
SWDIR
P00
P01
0
RUN/STOP
LAP
1
LAP
RUN/STOP