s3c2410a Samsung Semiconductor, Inc., s3c2410a Datasheet - Page 288

• Manufacturer Part Number: s3c2410a
• Description: 16/32-bit Risc Arm Microprocessor
• Manufacturer: Samsung Semiconductor, Inc.

PWM TIMER
TIMER OPERATION
Figure 10-4 shows the result of the following procedure:
1. Enable the auto reload function. Set the TCNTBn to 160 (50+110) and the TCMPBn to 110. Set the manual
2. Set the start bit, provided that manual_update is 0 and the inverter is off and auto reload is on. The timer starts
3. When the TCNTn has the same value as that of the TCMPn, the logic level of the TOUTn is changed from low to
4. When the TCNTn reaches 0, the interrupt request is generated and TCNTBn value is loaded into a temporary
5. In Interrupt Service Routine (ISR), the TCNTBn and the TCMPBn are set to 80 (20+60) and 60, respectively, for
6. When the TCNTn has the same value as the TCMPn, the logic level of TOUTn is changed from low to high.
7. When the TCNTn reaches 0, the TCNTn is reloaded automatically with the TCNTBn, triggering an interrupt
8. In Interrupt Service Routine (ISR), auto reload and interrupt request are disabled to stop the timer.
9. When the value of the TCNTn is same as the TCMPn, the logic level of the TOUTn is changed from low to high.
10. Even when the TCNTn reaches 0, the TCNTn is not any more reloaded and the timer is stopped because auto
11. No more interrupt requests are generated.
10-6
update bit and configure the inverter bit (on/off). The manual update bit sets TCNTn and TCMPn to the values of
TCNTBn and TCMPBn, respectively.
And then, set the TCNTBn and the TCMPBn to 80 (40+40) and 40, respectively, to determine the next reload
value.
counting down after latency time within the timer resolution.
high.
register. At the next timer tick, the TCNTn is reloaded with the temporary register value (TCNTBn).
the next duration.
request.
reload has been disabled.
TOUTn
Figure 10-4. Example of a Timer Operation
1
2
50
3
110
4
5
40
6
40
7 9
8
20
60
10
11
S3C2410A