Freescale Semiconductor, Inc.
Monitor Read-Only Memory (MON)
Functional Description
Table 10-8. RUN (Run User Program) Command
Description
Operand
Executes RTI instruction
None
None
$28
Data Returned
Opcode
Command Sequence
SENT TO
MONITOR
RUN
RUN
1
ECHO
Note 1 = Echo delay (2 bit times)
10.4.6 Baud Rate
With a 9.8304-MHz crystal, data is transferred between the monitor and
host at 9600 baud. If a 14.7456-MHz crystal is used, the monitor baud
rate is 9600.
NOTE: While in monitor mode with V applied to IRQ1, the MCU bus clock is
HI
always driven from the external clock.
10.4.7 Security
A security feature discourages unauthorized reading of FLASH locations
while in monitor mode. The host can bypass the security feature at
monitor mode entry by sending eight consecutive security bytes that
match the bytes at locations $FFF6–$FFFD. Locations $FFF6–$FFFD
contain user-defined data.
NOTE: Do not leave locations $FFF6–$FFFD blank. For security reasons,
program locations $FFF6–$FFFD even if they are not used for vectors.
If FLASH is unprogrammed, the eight security byte values to be sent are
$00, the unprogrammed state of the FLASH.
During monitor mode entry, the MCU waits after the power-on reset for
the host to send the eight security bytes on pin PA0.
MC68HC908RFRK2
MOTOROLA
AdvanceInformation
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Monitor Read-Only Memory (MON)
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