mc68hc908qf4 Freescale Semiconductor, Inc, mc68hc908qf4 Datasheet - Page 162

• Manufacturer Part Number: mc68hc908qf4
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Development Support
16.2.3 Low-Power Modes
16.3 Monitor Module (MON)
16.3.1 Functional Description
Data Sheet
162
The WAIT and STOP instructions put the MCU in low power- consumption standby
modes. If enabled, the break module will remain enabled in wait and stop modes.
However, since the internal address bus does not increment in these modes, a
break interrupt will never be triggered.
This subsection describes the monitor module (MON) and the monitor mode entry
methods. The monitor allows debugging and programming of the microcontroller
unit (MCU) through a single-wire interface with a host computer. Monitor mode
entry can be achieved without use of the higher test voltage, V
vector addresses $FFFE and $FFFF are blank, thus reducing the hardware
requirements for in-circuit programming.
Features include:
Figure 16-10
The monitor module receives and executes commands from a host computer.
Figure
enter monitor mode and communicate with a host computer via a standard RS-232
interface.
1. No security feature is absolutely secure. However, Motorola’s strategy is to make reading or
copying the FLASH difficult for unauthorized users.
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Normal user-mode pin functionality on most pins
One pin dedicated to serial communication between MCU and host
computer
Standard non-return-to-zero (NRZ) communication with host computer
Execution of code in random-access memory (RAM) or FLASH
FLASH memory security feature
FLASH memory programming interface
Use of external 9.8304 MHz oscillator to generate internal frequency of
2.4576 MHz
Simple internal oscillator mode of operation (no external clock or high
voltage)
Monitor mode entry without high voltage, V
($FFFE and $FFFF contain $FF)
Standard monitor mode entry if high voltage is applied to IRQ
Freescale Semiconductor, Inc.
16-11,
For More Information On This Product,
shows a simplified diagram of monitor mode entry.
Figure
Go to: www.freescale.com
Development Support
16-12, and
Figure 16-13
(1)
show example circuits used to
TST
, if reset vector is blank
MC68HC908QF4 — Rev. 1.0
TST
, as long as
MOTOROLA