C8051F02X Datasheet, PDF (238/272 Pages) Silicon Laboratories – 8K ISP FLASH MCU Family

C8051F020/1/2/3
Figure 22.14. T2CON: Timer 2 Control Register
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value
TF2
EXF2 RCLK0 TCLK0 EXEN2 TR2
C/T2 CP/RL2 00000000
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0 SFR Address:
(bit addressable) 0xC8
Bit7:
Bit6:
Bit5:
Bit4:
Bit3:
Bit2:
Bit1:
Bit0:
TF2: Timer 2 Overflow Flag.
Set by hardware when Timer 2 overflows. When the Timer 2 interrupt is enabled, setting this bit
causes the CPU to vector to the Timer 2 interrupt service routine. This bit is not automatically cleared
by hardware and must be cleared by software. TF2 will not be set when RCLK0 and/or TCLK0 are
logic 1.
EXF2: Timer 2 External Flag.
Set by hardware when either a capture or reload is caused by a high-to-low transition on the T2EX
input pin and EXEN2 is logic 1. When the Timer 2 interrupt is enabled, setting this bit causes the
CPU to vector to the Timer 2 Interrupt service routine. This bit is not automatically cleared by hard-
ware and must be cleared by software.
RCLK0: Receive Clock Flag for UART0.
Selects which timer is used for the UART0 receive clock in modes 1 or 3.
0: Timer 1 overflows used for receive clock.
1: Timer 2 overflows used for receive clock.
TCLK0: Transmit Clock Flag for UART0.
Selects which timer is used for the UART0 transmit clock in modes 1 or 3.
0: Timer 1 overflows used for transmit clock.
1: Timer 2 overflows used for transmit clock.
EXEN2: Timer 2 External Enable.
Enables high-to-low transitions on T2EX to trigger captures or reloads when Timer 2 is not operating
in Baud Rate Generator mode.
0: High-to-low transitions on T2EX ignored.
1: High-to-low transitions on T2EX cause a capture or reload.
TR2: Timer 2 Run Control.
This bit enables/disables Timer 2.
0: Timer 2 disabled.
1: Timer 2 enabled.
C/T2: Counter/Timer Select.
0: Timer Function: Timer 2 incremented by clock defined by T2M (CKCON.5).
1: Counter Function: Timer 2 incremented by high-to-low transitions on external input pin (T2).
CP/RL2: Capture/Reload Select.
This bit selects whether Timer 2 functions in capture or auto-reload mode. EXEN2 must be logic 1 for
high-to-low transitions on T2EX to be recognized and used to trigger captures or reloads. If RCLK0
or TCLK0 is set, this bit is ignored and Timer 2 will function in auto-reload mode.
0: Auto-reload on Timer 2 overflow or high-to-low transition at T2EX (EXEN2 = 1).
1: Capture on high-to-low transition at T2EX (EXEN2 = 1).
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Rev. 1.4