Freescale Semiconductor, Inc.
Ge ne ra l De sc rip tion
1.4.7 PD5 a nd PD7/ TCAP
These two I/O pins comprise port D and one of them is shared with the
16-bit timer subsystem. The state of PD5 is software programmable and
is configured as an input during power-on or reset. PD7 is always an
input. It may be read at any time, regardless of which mode of operation
the 16-bit timer is in. Refer to Section 6. Input/Output Ports and
Section 8. Capture/Compare Timer.
1.4.8 TCMP
This pin is the output from the 16-bit timer’s output compare function. It
is low after reset. Refer to Section 8. Capture/Compare Timer.
1.4.9 IRQ/ V (Ma ska b le Inte rrup t Re q ue st)
PP
This input pin drives the asynchronous interrupt function of the MCU in
user mode and provides the V programming voltage in bootloader
PP
mode. The MCU will complete the current instruction being executed
before it responds to the IRQ interrupt request. When the IRQ/V pin is
PP
driven low, the event is latched internally to signify an interrupt has been
requested. When the MCU completes its current instruction, the interrupt
latch is tested. If the interrupt latch is set and the interrupt mask bit (I bit)
in the condition code register is clear, the MCU will begin the interrupt
sequence.
Depending on the MOR LEVEL bit, the IRQ/V pin will trigger an
PP
interrupt on either a negative edge at the IRQ/V pin and/or while the
PP
IRQ/V pin is held in the low state. In either case, the IRQ/V pin must
PP
PP
be held low for at least one t
time period. If the edge- and level-
ILIH
sensitive mode is selected (LEVEL bit set), the IRQ/V input pin
PP
requires an external resistor connected to V for wired-OR operation.
DD
If the IRQ/V pin is not used, it must be tied to the V supply. The
PP
DD
IRQ/V pin input circuitry contains an internal Schmitt trigger to improve
PP
noise immunity. Refer to Section 5. Interrupts.
NOTE: If the voltage level applied to the IRQ/V pin exceeds V , it may affect
PP
DD
the MCU’s mode of operation. See Section 3. Operating Modes.
General Release Specification
MC68HC705P6A — Rev. 1.0
General Description
For More Information On This Product,
Go to: www.freescale.com
FREESCALE [ Freescale ]
