Texas Instruments TMS320C3x 사용자 설명서
Timers
12-10
12.1.6 Timer Operation Modes
The timer can receive its input and send its output in several different modes,
depending upon the setting of CLKSRC, FUNC, and I/O. The four timer modes
of operation are defined in the following sections.
depending upon the setting of CLKSRC, FUNC, and I/O. The four timer modes
of operation are defined in the following sections.
12.1.6.1
CLKSRC = 1 and FUNC = 0
If CLKSRC = 1 and FUNC = 0, the timer input comes from the internal clock.
The internal clock is not affected by the INV bit in the global-control register.
In this mode, TCLK is connected to the I/O port control, and you use TCLK as
a general-purpose I/O pin (see Figure 12–5).
The internal clock is not affected by the INV bit in the global-control register.
In this mode, TCLK is connected to the I/O port control, and you use TCLK as
a general-purpose I/O pin (see Figure 12–5).
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If I/O = 0, TCLK is configured as a general-purpose input pin whose state
you can read in DATIN. DATOUT has no effect on TCLK or DATIN. See
Figure 12–5 (a).
you can read in DATIN. DATOUT has no effect on TCLK or DATIN. See
Figure 12–5 (a).
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If I/O = 1, TCLK is configured as a general-purpose output pin. DATOUT
is placed on TCLK and can be read in DATIN. See Figure 12–5 (b).
is placed on TCLK and can be read in DATIN. See Figure 12–5 (b).
Figure 12–5. Timer Configuration with CLKSRC = 1 and FUNC = 0
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CLKSRC=1 (internal)
FUNC=0 (I/O pin)
I/O=0 (input)
I/O port
control
TCLK
External
Internal
Output
DATIN
Input
Internal
clock
clock
TSTAT
Timer
DATIN
DATOUT
Internal
External
TCLK
control
I/O port
Timer
TSTAT
clock
Internal
Output
Input
(a)
(b)
CLKSRC = 1 (internal)
FUNC = 0 (I/O pin)
I/O = 1 (output)