Sonic Alert msm80154s, msm83c154s, msm85c154hvs Timer 2 control register T2CON, TF2 EXF2, EXEN2

INTERNAL SPECIFICATIONS

4.4.2.9 Timer 2 control register (T2CON)

Name	Address	MSB							LSB
		7	6	5	4	3	2	1	0
TMOD	0C8H	TF2	EXF2	RCLK	TCLK	EXEN2	TR2	C/T2	CP/RL2
Bit location	Flag				Function
T2CON.0	CP/RL2	Capture mode is set when TCLK+RCLK="0" and CP/RL2 16-bit
		auto reload mode is set when TCLK+RCLK="0" and CP/RL2="0".
		CP/RL2 is ignored when TCLK+RCLK="1".
T2CON.1	C/T2	Timer/counter 2 count clock designation control bit.
		The internal clocks (XTAL1·2÷12, XTAL1·2÷2) are used when this
		bit is "0", and the external clock applied to the T2 pin is passed to
		timer/counter 2 when the bit is "1".
T2CON.2	TR2	Timer/counter 2 counting start and stop control bit.
		Timer/counter 2 commences counting when this bit is "1" and
		stops counting when "0".
T2CON.3	EXEN2	T2EX timer/counter 2 external control signal control bit. Input of the
		T2EX signal is disabled when this bit is "0", and enabled when "1".
T2CON.4	TCLK	Serial port transmit circuit drive clock control bit.
		Timer/counter 2 is switched to baud rate generator mode when this
		bit is "1", and the timer/counter 2 carry signal becomes the serial
		Port transmit clock. Note, however, that the serial ports can only
		use the timer/counter 2 carry signal in serial port modes 1 and 3.
T2CON.5	RCLK	Serial port receive circuit drive clock control bit.
		Timer/counter 2 is switched to baud rate generator mode when this
		bit is "1", and the timer/counter 2 carry signal becomes the serial
		Port receive clock. Note, however, that the serial ports can only
		use the timer/counter 2 carry signal in serial port modes 1 and 3.
T2CON.6	EXF2	Timer/counter 2 external flag.
		This bit is set to "1" when the T2EX timer/counter 2 external
		control signal level is changed from "1" to "0" while EXEN2="1".
		This flag serves as the timer interrupt 2 request signal. if an
		interrupt is generated, it must be reset to "0" by software.
T2CON.7	TF2	Timer/counter 2 carry flag.
		This bit is set to "1" by a carry signal when timer/counter 2 is in 16-
		bit auto reload mode or in capture mode.
		This flag serves as the timer interrupt 2 request signal. if an
		interrupt is generated, it must be reset to "0" by software.

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