MC68HC708XL36 FREESCALE [Freescale Semiconductor, Inc], MC68HC708XL36 Datasheet - Page 169

• Manufacturer Part Number: MC68HC708XL36
• Description: HCMOS Microcontroller Unit
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Security
13-mon08sp_1p
MOTOROLA
NOTE:
A security feature discourages unauthorized reading of EPROM
locations while in monitor mode. The host can bypass the security
feature at monitor mode entry by sending eight security bytes that match
the bytes at locations $FFF6–$FFFD. Locations $FFF6–$FFFD contain
user-defined data.
Do not leave locations $FFF6–$FFFD blank. For security reasons,
program 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.
V
RST
PA7
PA0
NOTE: 1 = Echo delay (2 bit times)
DD
Freescale Semiconductor, Inc.
For More Information On This Product,
2 = Data return delay (2 bit times)
4 = Wait 1 bit time before sending next byte.
Go to: www.freescale.com
FROM HOST
FROM MCU
4096 + 32 CGMXCLK CYCLES
Figure 7. Monitor Mode Entry Timing
24 CGMXCLK CYCLES
MON
1
256 CGMXCLK CYCLES (ONE BIT TIME)
4
1
1
2
MC68HC708XL36
4
1
Security
MON
169