Freescale Semiconductor Microcontrollers, Руководство пользователя

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ICS MON08 Interface Connection
Device Class Description
362 Microcontrollers Debugger Manual
Class 2 Device
ICS Board without processor, connected to the user’s microprocessor system via MON08
Cable. In this configuration, there is no processor resident in any of the sockets of the ICS
board itself. The processor is mounted down in the user’s MCU system. The connection
from the ICS board to the user’s MCU system is accomplished via the 16-pin MON08
connector. In this configuration, since the ICS does not control power to the processor, the
user is prompted to turn the processor's power supply on and off. Turning off the power
supply is necessary to pass the initial security mode check and access the Flash on the
processor. A simple reset is not enough; to pass the security check, you must first force the
processor to encounter a POR (power-on reset) which requires that the processor's voltage
dip below 0.1v. Once security is passed, resetting the device or re-entering the software is
easier.
Class 3 Device
Custom Board (no ICS) with MON08 serial port circuitry built in. In this configuration,
the ICS board is not used at all. The user must provide a serial port connection from the
PC, and provide all hardware configuration necessary to force the processor into MON08
mode upon reset. This includes resets both internal and external to the processor. In this
configuration, because the software does not directly control power to the processor, the
user is prompted to turn the processor's power supply on and off. The user is also
prompted to turn power on and off to reset the microprocessor, as the PC has no control of
the microprocessor reset. Turning off the power supply is necessary to pass the initial
security mode check and access the Flash on the processor. A simple reset is not enough;
to pass the security check, you must first force the processor to encounter a POR (power-
on reset) which requires that the processor's voltage dip below 0.1v. Once security is
passed, resetting the device or re-entering the software is easier. Class 3 selection also
applies to use of the ICS board with the two-pin blank part programming connector.
Class 4 Device
Custom Board (no ICS) with MON08 serial port circuitry and additional auto-reset circuit
built in. In this configuration, the ICS board is not used at all. The user must provide a
serial port connection from the PC and all hardware configuration necessary to force the
processor into MON08 mode upon reset. In addition, the user must include an extra circuit
which allows the reset line of the processor to be driven low from the DTR line of the
serial port connector (Pin 4 on a DB9). The following diagram shows the additional
connection needed to reset from a DB9 serial connector.