Oki MSM83C154S, MSM80C154S manual Special Function Registers Timer mode register Tmod, Gate

¡ Semiconductor MSM80C154S/83C154S

Special Function Registers

Timer mode register (TMOD)

NAME	ADDRESS	MSB							LSB
		7	6	5	4	3	2	1	0
TMOD	89H	GATE	C/T	M1	M0	GATE	C/T	M1	M0
BIT LOCATION	FLAG				FUNCTION
TMOD.0	M0	M1	M0	Timer/counter 0 mode setting
		0	0	8-bit timer/counter with 5-bit prescalar.
		0	1	16-bit timer/counter.
		1	0	8-bit timer/counter with 8-bit auto reloading.
				Timer/counter 0 separated into TLO (8-bit) timer/counter
TMOD.1	M1	1	1
				and TH0 (8-bit) timer/counter. TF0 is set by TL0 carry, and
				TF1 is set by TH0 carry.
TMOD.2	C/T	Timer/counter 0 count clock designation control bit.
		XTAL1•2 divided by 12 clocks is the input applied to timer/counter 0 when
		C/T = "0".
		The external clock applied to the T0 pin is the input applied to timer/counter 0
		when C/T = "1".
TMOD.3	GATE	When this bit is "0", the TR0 bit of TCON (timer control register) is used to
		control the start and stop of timer/counter 0 counting.
		If this bit is "1", timer/counter 0 starts counting when both the TR0 bit of TCON
		and INT0 pin input signal are "1", and stops counting when either is changed
		to "0".
TMOD.4	M0	M1	M0	Timer/counter 1 mode setting
		0	0	8-bit timer/counter with 5-bit prescalar.
		0	1	16-bit timer/counter
		1	0	8-bit timer/counter with 8-bit auto reloading.
TMOD.5	M1
		1	1	Timer/counter 1 operation stopped.
TMOD.6	C/T	Timer/counter 1 count clock designation control bit.
		XTAL1•2 divided by 12 clocks is the input applied to timer/counter 1 when
		C/T = "0".
		The external clock applied to the T1 pin is the input applied to timer/counter 1
		when C/T = "1".
TMOD.7	GATE	When this bit is "0", the TR1 bit of TCON is used to control the start and stop of
		timer/counter 1 counting.
		If this bit is "1", timer/counter 1 starts counting when both the TR1 bit of TCON
		and INT1 pin input signal are "1", and stops counting when either is changed
		to "0".

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