By:
Masud-ul-Hasan
9
Timer Modes (cont'd)
•Timer Mode
3:
–Timer
0 Splits into two 8-bit counter/timers. TL0 and TH0 act as two separate timers with
overflows setting the TF0 and TF1 respectively.
–Timer
1 (when timer 0 is in mode 3 ):
§Counter stopped
if in mode 3
§Can be used in
mode 0, 1, or 2
§Has gate (INT1)
and external input (T1), but no flag or interrupt.
§May be used as a
baud rate generator.
Timer
clock
clock
TH1
8-bits
8-bits
TL1
8-bits
8-bits
Overflow
flag
Timer
clock
clock
TF0
Interrupt
TL0
8-bits
8-bits
Overflow
flag
÷12 Fosc.
TF1
Interrupt
TH0
8-bits
8-bits