Samsung S3F80JB, Руководство пользователя

Страница: 110 / 346

S3F80JB CONTROL REGISTERS
4-43
T2CON
— Timer 2 Control Register E8H Set1 Bank1
Bit Identifier .7 .6 .5 .4 .3 .2 .1 .0
Reset Value 0 0 0 0 0 0 0 0
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Addressing Mode Register addressing mode only
.7 and .6 Timer 2 Input Clock Selection Bits
0 0
f
OSC
/4
0 1
f
OSC
/8
1 0 f
OSC
/16
1 1 Internal clock (counter A flip-flop, T-FF)
.5 and .4 Timer 2 Operating Mode Selection Bits
0 0 Interval timer mode (counter cleared by match signal)
0 1 Capture mode (rising edges, counter running, OVF can occur)
1 0 Capture mode (falling edges, counter running, OVF can occur)
1 1 Capture mode (rising and falling edges, counter running, OVF can occur)
.3 Timer 2 Counter Clear Bit
0 No effect (when write)
1 Clear T2 counter, T2CNT (when write)
.2 Timer 2 Overflow Interrupt Enable Bit (note)
0 Disable T2 overflow interrupt
1 Enable T2 overflow interrupt
.1 Timer 2 Match/Capture Interrupt Enable Bit
0 Disable T2 match/capture interrupt
1 Enable T2 match/capture interrupt
.0 Timer 2 Match/Capture Interrupt Pending Flag Bit
0 No T2 match/capture interrupt pending (when read)
0 Clear T2 match/capture interrupt pending condition (when write)
1 T2 match/capture interrupt is pending (when read)
1 No effect (when write)
NOTE : A timer 2 overflow interrupt pending condition is automatically cleared by hardware. However, the timer 2 match/
capture interrupt, IRQ3, vector F2H, must be cleared by the interrupt service routine (S/W).