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ICS MON08 Interface Connection
Connection Procedure
356 Microcontrollers Debugger Manual
This status indicates whether or not the first echoed character from the hardware
loopback was received when one of the security bytes was transmitted. If the status is
‘N’, which indicates that the character was not received, it is most likely due to one
of the following reasons:
– Wrong Com Port specified.
– The baud rate specified was incorrect (probably too low).
– The ICS/Target is not connected.
– No Power to the ICS.
If this status bit returns an ‘N’, you must correct this before analyzing the reset of the
status bits.
• 1 – Device echoed some security bytes:
The monitor resident in a M68HC08 device automatically echoes every incoming
character when it is in monitor mode. A valid character transmitted from the PC is
echoed once by the loopback circuitry on the board and once by the monitor of the
target processor itself. This status indicates whether or not the second echoed
character from the monitor response was received when one of the security bytes was
transmitted. If the status is ‘N’, which indicates that the character was not received,
or not received properly, it is most likely due to one of the following reasons:
– The baud rate specified was incorrect.
– The part did not start the monitor mode security check on reset. Signals to force
monitor mode may be incorrect.
– No Power to the ICS.
If this status bit returns an ‘N’, you must correct this before analyzing the reset of the
status bits.
• 2 – Device echoed all security bytes:
To pass security, the software must send eight security bytes to the processor. The
processor echoes each of these eight bytes twice. If all eight bytes did not get the
proper two-byte echo, this flag returns an ‘N’. Reasons for this include:
– The part did not start the monitor mode security check on reset. Signals to force
monitor mode may be incorrect.
– The baud rate specified was incorrect.
– The processor was not reset properly. Check the Target Hardware Type and if
you are connecting to a class II board, check the MON08 cable communication
connections type in the Advanced Settings dialog box.
• 3 – Device signaled monitor mode with a break:
Once the processor has properly received the eight bytes from the PC software to
complete its security check, it transmits a break character to the PC signaling entry
into monitor mode. This break character is sent regardless of whether the security