MC68HC08AZ60ACFU MOTOROLA [Motorola, Inc], MC68HC08AZ60ACFU Datasheet - Page 186

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

Monitor ROM (MON)
12.4.6 Security
Advance Information
186
NOTE:
outlines the available baud rates for a range of crystals and how they can
match to a PC baud rate.
Care should be taken when setting the baud rate since incorrect
baud rate setting can result in communications failure.
Security features discourage unauthorized reading of ROM/EEPROM
locations while in monitor mode. The host can bypass the security
features at monitor mode entry by sending eight security bytes that
match the byte locations $FFF6–$FFFD. Locations $FFF6–$FFFD
contain user-defined data.
Do not leave locations $FFF6–$FFFD blank. For security reasons, enter
data at locations $FFF6–$FFFD even if they are not used for vectors.
During monitor mode entry, the MCU waits after the power-on reset for
the host to send the eight security bytes on pin PA0.
If the received bytes match those at locations $FFF6–$FFFD, the host
bypasses the security features and can read all ROM/EEPROM
locations and execute code from ROM. Security remains bypassed until
a power-on reset occurs. After the host bypasses security, any reset
other than a power-on reset requires the host to send another eight
4.9152MHz
Clock freq
4.194MHz
16MHz
32kHz
1MHz
2MHz
4MHz
8MHz
14492.72
28985.51
PTC3=0
1811.59
3623.19
7246.37
7597.83
8904.35
57.97
Monitor ROM (MON)
Baud rate
14492.75
PTC3=1
3623.19
3798.91
4452.17
7246.37
1811.59
905.80
28.98
Closest PC baud PC
PTC3=0
14400
28800
1800
3600
7200
7680
8861
57.6
PTC3=1
14400
1800
3600
3840
4430
7200
28.8
900
MC68HC08AZ60A — Rev 0.0
PTC3=0
0.64
0.64
0.64
0.64
1.08
0.49
0.64
0.64
Error %
MOTOROLA
PTC3=1
0.63
0.64
0.64
0.64
1.08
0.50
0.64
0.64