MC68HC08AZ60ACFU MOTOROLA [Motorola, Inc], MC68HC08AZ60ACFU Datasheet - Page 187

• Manufacturer Part Number: MC68HC08AZ60ACFU
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

MC68HC08AZ60A — Rev 0.0
MOTOROLA
NOTE:
bytes. If the reset was not a power-on reset, security remains bypassed
regardless of the data that the host sends.
If the received bytes do not match the data at locations $FFF6–$FFFD,
the host fails to bypass the security features. The MCU remains in
monitor mode, but reading ROM/EEPROM locations returns undefined
data, and trying to execute code from ROM causes an illegal address
reset. After the host fails to bypass security, any reset other than a
power-on reset causes an endless loop of illegal address resets.
After receiving the eight security bytes from the host, the MCU transmits
a break character signalling that it is ready to receive a command.
The MCU does not transmit a break character until after the host sends
the eight security bytes.
V
RST
NOTE: 1 = Echo delay (2 bit times)
DD
PA0
2 = Data return delay (2 bit times)
4 = Wait 1 bit time before sending next byte.
Figure 12-6. Monitor Mode Entry Timing
FROM HOST
Monitor ROM (MON)
FROM MCU
4096 + 32 CGMXCLK CYCLES
1
24 BUS CYCLES (MINIMUM)
4
1
1
Functional description
Monitor ROM (MON)
Advance Information
2
4
1
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