Intel MCS 51

intd.
M@@.51 PROGRAMMERS GUIDEAND INSTRUCTION SET
TIMER/COUNTER 1
As a Time~
Table 5
TMOD
MODE
TIMER 1
INTERNAL EXTERNAL
FUNCTION
CONTROL
CONTROL
(NOTE 1) (NOTE 2)
o 13-bitTimer
OOH
80H
1
16-bitTimer 10H
90H
2 8-bitAuto-Reload 20H AOH
3
does notrun 30H
BOH
As a Counter:
Table 6
o 13-bitTimer 40H WH
1
16-bitTimer
50H
DOH
2 8-bitAuto-Reload
60H
EOH
3 notavailable
— —
NOTES
1.TheTimeristurnedON/OFFbysetting/claaringbitTR1inthesoftware.
2. TheTimeristurnedON/OFFbythe 1 to Otransitionon~ (P3.3)whenTR1 = 1
(hardwerecontrol).
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