16-BIT TIMER 0/1
S3C8248/C8245/P8245/C8247/C8249/P8249
12-2
TIMER 0 CONTROL REGISTER (T0CON)
You use the timer 0 control register, T0CON, to
— Enable the timer 0 operating (interval timer)
— Select the timer 0 input clock frequency
— Clear the timer 0 counter, T0CNT
— Enable the timer 0 interrupt and clear timer 0 interrupt pending condition
T0CON is located in set 1, at address F1H, and is read/write addressable using register addressing mode.
A reset clears T0CON to "00H". This sets timer 0 to disable interval timer mode, selects the TBOF, and disables
timer 0 interrupt. You can clear the timer 0 counter at any time during normal operation by writing a “1” to
T0CON.3
To enable the timer 0 interrupt (IRQ2, vector E6H), you must write T0CON.2, and T0CON.1 to "1". To generate
the exact time interval, you should write T0CON.3 and 0, which cleared counter and interrupt pending bit. To
detect an interrupt pending condition when T0INT is disabled, the application program polls pending bit,
T0CON.0. When a "1" is detected, a timer 0 interrupt is pending. When the T0INT sub-routine has been serviced,
the pending condition must be cleared by software by writing a "0" to the timer 0 interrupt pending bit, T0CON.0.
Timer 0 Control Registers
F1H, Set 1, Bank 1, R/W, RESET; 00H
.7
.6
.5
.4
.3
.2
.1
.0
MSB
LSB
Timer 0 interrupt enable bit:
0 = Disable interrupt
1 = Enable interrupt
Timer 0 interrupt pending bit:
0 = No interrupt pending
0 = Clear pending bit (when write)
1
=
Interrupt is pending
Timer 0 count enable bit:
0 = Disable counting operation
1 = Enable counting operation
Timer 0 counter clear bit:
0 = No affect
1 = Clear the timer 0 counter
(when write)
Timer 0 input clock selection bits:
000 = TBOF
010 = f
XX
/256
100 = f
XX
/64
110 = f
XX
/8
XX
1 = f
XX
Not used
NOTE:
For normal operation T0CON.3 bit must be set 1.
Figure 12-1. Timer 0 Control Register (T0CON)
Summary of Contents for S3C8248
Page 31: ...ADDRESS SPACES S3C8248 C8245 P8245 C8247 C8249 P8249 2 20 NOTES ...
Page 107: ...INTERRUPT STRUCTURE S3C8248 C8245 P8245 C8247 C8249 P8249 5 18 NOTES ...
Page 195: ...INSTRUCTION SET S3C8248 C8245 P8245 C8247 C8249 P8249 6 88 NOTES ...
Page 221: ...I O PORTS S3C8248 C8245 P8245 C8247 C8249 P8249 9 16 NOTES ...
Page 245: ...16 BIT TIMER 0 1 S3C8248 C8245 P8245 C8247 C8249 P8249 12 10 NOTES ...
Page 249: ...WATCH TIMER S3C8248 C8245 P8245 C8247 C8249 P8249 13 4 NOTES ...
Page 267: ...A D CONVERTER S3C8248 C8245 P8245 C8247 C8249 P8249 15 6 NOTES ...
Page 299: ...S3P8245 P8249 OTP S3C8248 C8245 P8245 C8247 C8249 P8249 21 8 NOTES ...
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