Analog Devices ADuC812 manual C8H, TF2, EXF2, Rclk, Tclk, EXEN2, TR2, CNT2, CAP2

ADuC812

T2CON	Timer/Counter 2 Control Register
SFR Address	C8H
Power-On Default Value	00H
Bit Addressable	Yes

TF2

EXF2

RCLK

TCLK

EXEN2

TR2

CNT2

CAP2

		Table XVIII. T2CON SFR Bit Designations
Bit	Name	Description
7	TF2	Timer 2 Overflow Flag.
		Set by hardware on a timer 2 overflow. TF2 will not be set when either RCLK or TCLK = 1.
		Cleared by user software.
6	EXF2	Timer 2 External Flag.
		Set by hardware when either a capture or reload is caused by a negative transition on T2EX and
		EXEN2 = 1.
		Cleared by user software.
5	RCLK	Receive Clock Enable Bit.
		Set by user to enable the serial port to use timer 2 overflow pulses for its receive clock in serial port
		Modes 1 and 3.
		Cleared by user to enable timer 1 overflow to be used for the receive clock.
4	TCLK	Transmit Clock Enable Bit.
		Set by user to enable the serial port to use timer 2 overflow pulses for its transmit clock in serial
		port Modes 1 and 3.
		Cleared by user to enable timer 1 overflow to be used for the transmit clock.
3	EXEN2	Timer 2 External Enable Flag.
		Set by user to enable a capture or reload to occur as a result of a negative transition on T2EX if
		Timer 2 is not being used to clock the serial port.
		Cleared by user for Timer 2 to ignore events at T2EX.
2	TR2	Timer 2 Start/Stop Control Bit.
		Set by user to start timer 2.
		Cleared by user to stop timer 2.
1	CNT2	Timer 2 Timer or Counter Function Select Bit.
		Set by user to select counter function (input from external T2 pin).
		Cleared by user to select timer function (input from on-chip core clock).
0	CAP2	Timer 2 Capture/Reload Select Bit.
		Set by user to enable captures on negative transitions at T2EX if EXEN2 = 1.
		Cleared by user to enable auto-reloads with Timer 2 overflows or negative transitions at T2EX
		when EXEN2 = 1. When either RCLK = 1 or TCLK = 1, this bit is ignored and the timer is
		forced to autoreload on Timer 2 overflow.

Timer/Counter 2 Data Registers

Timer/Counter 2 also has two pairs of 8-bit data registers associated with it. These are used as both timer data registers and timer capture/reload registers.

TH2 and TL2

Timer 2, data high byte and low byte.

SFR Address = CDH, CCH respectively.

RCAP2H and RCAP2L

Timer 2, Capture/Reload byte and low byte.

SFR Address = CBH, CAH respectively.

REV. B –33–