Intel 80C196NU, 8XC196NP, Microcontroller manual TIMER1, TIMER2

8XC196NP, 80C196NU USER’S MANUAL

Table 10-2. EPA Control and Status Registers (Continued)

Mnemonic	Address	Description
P1_MODE	1FD0H	Port 1 Mode
		Each bit of P1_MODE controls whether the corresponding pin
		functions as a standard I/O port pin or as a special-function
		signal. Setting a bit configures a pin as a special-function signal;
		clearing a bit configures a pin as a standard I/O port pin.
P1_PIN	1FD6H	Port 1 Input
		Each bit of P1_PIN reflects the current state of the corresponding
		pin, regardless of the pin configuration.
P1_REG	1FD4H	Port 1 Data Output
		For an input, set the corresponding P1_REG bit.
		For an output, write the data to be driven out by each pin to the
		corresponding bit of P1_REG. When a pin is configured as
		standard I/O (P1_MODE.y = 0), the result of a CPU write to
		Px_REG is immediately visible on the pin. When a pin is
		configured as a special-function signal (P1_MODE.y = 1), the
		associated on-chip peripheral or off-chip component controls the
		pin. The CPU can still write to P1_REG, but the pin is unaffected
		until it is switched back to its standard I/O function.
		This feature allows software to configure a pin as standard I/O
		(clear P1_MODE.y), initialize or overwrite the pin value, then
		configure the pin as a special-function signal (set P1_MODE.y). In
		this way, initialization, fault recovery, exception handling, etc., can
		be done without changing the operation of the associated
		peripheral.
T1CONTROL	1F90H	Timer 1 Control
		This register enables/disables timer 1, controls whether it counts
		up or down, selects the clock source and direction, and
		determines the clock prescaler setting.
T2CONTROL	1F94H	Timer 2 Control
		This register enables/disables timer 2, controls whether it counts
		up or down, selects the clock source and direction, and
		determines the clock prescaler setting.
TIMER1	1F92H	Timer 1 Value
		This register contains the current value of timer 1.
TIMER2	1F96H	Timer 2 Value
		This register contains the current value of timer 2.

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