IS80C52 Datasheet, PDF (14/48 Pages) Integrated Silicon Solution, Inc – CMOS SINGLE CHIP LOW VOLTAGE 8-BIT MICROCONTROLLER

IS80C52
IS80C32
ISSI ^®
T2CON:
Timer/Counter 2 Control Register. Bit Addressable.
7
65
4
3
2
10
TF2 EXF2 RCLK TCLK EXEN2 TR2 C/T2 CP/RL2
Register Description:
TF2 T2CON.7 Timer 2 overflow flag set by hardware
and cleared by software. TF2 cannot
be set when either RCLK = 1 or TCLK
= 1.
EXF2 T2CON.6 Timer 2 external flag set when either a
capture or reload is caused by a
negative transition on T2EX, and
EXEN2 = 1. When Timer 2 interrupt is
enabled, EXF2 = 1 causes the CPU to
vector to the Timer 2 interrupt routine.
EXF2 must be cleared by software.
RCLK T2CON.5 Receive clock flag. When set, causes
the Serial Port to use Timer 2 overflow
pulses for its receive clock in modes 1
and 3. RCLK = 0 causes Timer 1
overflow to be used for the receive
clock.
TLCK T2CON.4 Transmit clock flag. When set, causes
the Serial Port to use Timer 2 overflow
pulses for its transmit clock in modes
1 and 3. TCLK = 0 causes Timer 1
overflows to be used for the transmit
clock.
EXEN2 T2CON.3 Timer 2 external enable flag. When
set, allows a capture or reload to occur
as a result of negative transition on
T2EX if Timer 2 is not being used to
clock the Serial Port, EXEN2 = 0
causes Timer 2 to ignore events at
T2EX.
TR2 T2CON.2 Software START/STOP control for
Timer 2. A logic 1 starts the Timer.
C/T2 T2CON.1 Timer or Counter select. 0 = Internal
Timer. 1 = External Event Counter
(triggered by falling edge).
CP/RL2 T2CON.0 Capture/Reload flag. When set,
captures occur on negative transitions
at T2EX if EXEN2 = 1. When cleared,
auto-reloads occur either 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
auto-reload on Timer 2 overflow.
Notes:
1. Timer 2 Operating Modes
RCLK + TCLKCP/RL2 TR2
0
0
1
0
1
1
1
X
1
X
X
0
MODE
16-Bit Auto-Reload
16-Bit Capture
Baud Rate Generator
(Off)
2. User software should not write 1s to reserved bits. These bits
may be used in future products to invoke new features.
14
Integrated Silicon Solution, Inc. — 1-800-379-4774
MC004-1D
11/19/98