MC68HC705KJ1CS FREESCALE [Freescale Semiconductor, Inc], MC68HC705KJ1CS Datasheet - Page 12

• Manufacturer Part Number: MC68HC705KJ1CS
• Description: Migrating from the MC68HC705K1 to the MC68HC705KJ1
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Application Note
Reset and LVR
Circuitry
Interrupts
For applications that demand more performance, the KJ1 maximum
internal clock frequency is 4 MHz. The K1 maximum internal clock
frequency is 2 MHz.
The reset function on the KJ1 has additional features:
The KJ1 does not have an internal LVR. If your K1 design used the LVR,
external LVR circuitry must be added to replace this function.
Like the K1, the KJ1 has the same interrupt sources and functionality.
These are:
The port A interrupt option on the K1 is programmed by writing to the
PIRQ bit (bit 2) of the MOR at location $17. On the KJ1, write to the PIRQ
bit (bit 2) of the MOR at location $7F1.
The external interrupt sensitivity on the K1 is programmed by writing to
the LEVEL bit (bit 1) of the MOR at location $17. On the KJ1, write to the
LEVEL bit (bit 1) of the MOR at location $7F1.
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Freescale Semiconductor, Inc.
For More Information On This Product,
The RESET pin contains a steering diode to discharge any voltage
on the pin to V
The RESET pin contains an internal pullup resistor to V
the RESET pin to be left unconnected for low-power applications.
The KJ1 has all of the K1 reset sources except a low-voltage reset
(LVR). These are:
– Power-on reset
– Logic 0 on the RESET pin
– Computer operating properly (COP)
– Illegal address
Software interrupt
Logic 0 applied to the IRQ/V
Logic 1 applied to one of the PA3–PA0 pins
A timer overflow interrupt
A real-time interrupt
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DD
when the power is removed.
PP
pin
DD
to allow
AN1746