MC68HC711PH8 Motorola, MC68HC711PH8 Datasheet - Page 138

• Manufacturer Part Number: MC68HC711PH8
• Description: High-density Complementary Metal Oxide Semiconductor (HCMOS) Microcomputer Unit
• Manufacturer: Motorola

8
T16EN — 16-bit timer clock enable
Power consumption may be reduced by disabling the 16-bit timer clock. This bit cannot be cleared
whilst VDDSYN is low, as then the 16-bit timer provides the clock source for the COP and RTI.
When VDDSYN is high, the 8-bit modulus timer A supplies the clock source for the COP and RTI
functions, which are therefore independent from the 16-bit timer clock. Reset sets this bit.
WEN — WAIT enable (See Section 2.5.4.1)
8.1.2
The timer functions share I/O with all eight pins of port A:
Figure 8-3 shows the capture/compare system block diagram. The port A pin control block
includes logic for timer functions and for general-purpose I/O. For pins PA3, PA2, PA1 and PA0,
this block contains both the edge-detection logic and the control logic that enables the selection
of which edge triggers an input capture. The digital level on PA[3:0] can be read at any time (read
PORTA register), even if the pin is being used for the input capture function. Pins PA[6:3] are used
either for general-purpose I/O, or as output compare pins. When one of these pins is being used
for an output compare function, it cannot be written directly as if it were a general-purpose output.
Each of the output compare functions (OC[5:2]) is related to one of the port A output pins. Output
compare 1 (OC1) has extra control logic, allowing it optional control of any combination of the
PA[7:3] pins. The PA7 pin can be used as a general-purpose I/O pin, as an input to the pulse
accumulator or as an OC1 output pin.
MOTOROLA
8-4
1 (set)
0 (clear) –
1 (set)
0 (clear) –
Timer structure
–
–
16-bit timer clock enabled.
16-bit timer clock disabled.
Low-power WAIT mode selected (PLL set to ‘idle’ in WAIT mode).
Do not alter the 4XCLK during WAIT mode.
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
Pin
TIMING SYSTEM
IC3
IC2
IC1
OC5 and/or OC1, or IC4
OC4 and/or OC1
OC3 and/or OC1
OC2 and/or OC1
PAI and/or OC1
Alternate function
MC68HC11PH8
TPG