Renesas rl78 User Manual

Page of 1004
 
RL78/G1A 
 
CHAPTER  8   INTERVAL  TIMER 
8.4  12-bit Interval Timer Operation 
 
8.4.1  12-bit interval timer operation timing  
The count value specified for the ITCMP11 to ITCMP0 bits is used as an interval to operate as a 12-bit interval timer 
that repeatedly generates interrupt requests (INTIT). 
When the RINTE bit is set to 1, the 12-bit counter starts counting. 
When the 12-bit counter value matches the value specified for the ITCMP11 to ITCMP0 bits, the 12-bit counter value is 
cleared to 0, counting continues, and an interrupt request signal (INTIT) is generated at the same time. 
 
The basic operation of the 12-bit interval timer is as follows. 
 
Figure 8-5.  12-bit Interval Timer Operation Timing (ITCMP11 to ITCMP0 = 0FFH, count clock: f
SUB
 = 32.768 kHz) 
 
INTIT
RINTE
0FFH
000H
0FFH
ITMCMP11 to
ITMCMP0
Count clock
12-bit counter
Period (7.81 ms)
After RINTE is changed from 0 to 1, counting starts 
at the rising edge of the next count clock signal.
When RINTE is changed from 1 to 0, 
the 12-bit counter is cleared without 
synchronization with the count clock.
 
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R01UH0305EJ0200  Rev.2.00 
 
 
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Jul 04, 2013