S1C63656 TECHNICAL MANUAL
EPSON
67
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Stopwatch Timer)
Direct RUN and direct LAP interrupts
When the direct input function is selected, the direct RUN and direct LAP interrupts can be generated.
The respective interrupts occur at the rising edge of the internal signal for direct RUN and direct LAP
after sampling the direct input signal in the falling edge of 1,024 Hz signal. Also, at this time the
corresponding interrupt factor flag (IRUN, ILAP) is set to "1".
The respective interrupts can be masked separately through the interrupt mask registers (EIRUN,
EILAP). However, regardless of the setting of the interrupt mask registers, the interrupt factor flags
are set to "1" by the inputs of the RUN and LAP.
The direct RUN and LAP functions use the K00 and K01 ports. Therefore, the direct input interrupt
and the K00–K03 inputs interrupt may generate at the same time depending on the interrupt condi-
tion setting for the input port K00–K03. Consequently, when using the direct input interrupt, set the
interrupt selection registers SIK00 and SIK01 to "0" so that the input interrupt does not generate by
K00 and K01 inputs.
f
OSC1
/32 (1,024 Hz)
SWRST writing
EDIR writing
EDIR register
Direct RUN input
SWRUN writing
SWRUN register
Direct LAP input
Counter data
Capture buffer
SWD0–3 reading
SWD4–7 reading
SWD8–11 reading
CRNWF
1 Hz interrupt factor flag ISW1
LCURF
Direct RUN interrupt
Direct LAP interrupt
10 Hz interrupt
1 Hz interrupt
001 002 003 004 005 006 098 099 100 101 102
000
001 002 003 004 005 006 007 993 994
000
995 996 997 998 999 000 001 002 003 004 005 006
007
003
005
995
001
006
Fig. 4.9.6.2 Timing chart for stopwatch timer
