Analog Devices ADuC812 - Manual (Page 33)

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ADuC812
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T2CON Timer/Counter 2 Control Register
SFR Address C8H
Power-On Default Value 00H
Bit Addressable Yes
2 F T 2 F X E K L C R K L C T 2 N E X E 2 R T 2 T N C 2 P A C
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.