mc68hc05pl4b Freescale Semiconductor, Inc, mc68hc05pl4b Datasheet - Page 38

• Manufacturer Part Number: mc68hc05pl4b
• Description: Low-cost Single-chip Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

GENERAL RELEASE SPECIFICATION
5.4.5 Keyboard Interrupt Interface
5.4.6 6-bit DAC Subsystem
5.4.7 System Clock Option Subsystem
5.4.8 Miscellaneous Subsystem
5-6
Therefore con gure the por t A pins PA2,PA3 as general I/O function. However the
timer is free running for interrupt process.
A reset has the following effects on the Keyboard Interrupt interface:
Therefore disables the Keyboard interrupt and leaves the shared port B pins as
general I/O. Any pending interrupt ag is cleared and the K eyboard interrupt is dis-
abled.
A reset has the following effects on the DAC subsystem:
Therefore con gure the por t A pin PA1 as general I/O function.
At reset has the following effects on OSC clock subsystem
A P reset has the following effects on IRQ subsystem
Therefore also disable the LED driver output, hence the LED/IRQ pin is in high
impedance state.
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Does not affect the input capture edge bit (IEDG) in the TCR.
Does not affect the interrupt ags in the timer status register (TSR).
Does not affect the input capture registers (ICRH, ICRL).
Does not affect the output compare registers (OCRH, OCRL).
Clears all bits in Keyboard interrupt enable register (KIER) and
Keyboard interrupt disable
Clears all bits in Keyboard interrupt ag register (KIFR)
Clears all bits in Pull-Up enable register (PUER)
Clears all bits in DAC control Register, hence DAC subsystem is
disabled.
The internal RC is enabled and oscillating at around 500kHz
Internal clock divider selected to divide by 2 for bus frequency
IRQ is disabled and reset the IRQ selection as negative edge-triggered
and low level-triggered, hence the LED/IRQ pin function as LED output
pin
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
April 30, 1998
RESETS
MC68HC05PL4
REV 2.0