AN1836 Motorola / Freescale Semiconductor, AN1836 Datasheet - Page 5

• Manufacturer Part Number: AN1836
• Description: FLASH Programming for Motorola MC68HC912 Microcontrollers
• Manufacturer: Motorola / Freescale Semiconductor

Hardware Configuration
Setting Up
the Debugging
Hardware
Setting Up the
M68HC12B32EVB
AN1836
MOTOROLA
Since programming the FLASH EEPROM takes a finite amount of time
and is dependent on a reliable programming voltage from an exterior
source, it is difficult to tell if the procedure worked immediately. Also, it
should be verified by some sort of external signal. To simplify the
debugging of the process, try using a few hardware techniques that are
listed in this application note.
For debugging hardware, simply use light-emitting diodes (LED),
connected to port pins on the MC68HC912B32 device to use as error
and sequence successfully complete indicators. For use with the code
listed here, connect a red LED to PA0, with a 1-k current limiting
resistor to indicate errors. In like manner, connect a green LED to PA1
to indicate that the process has completed successfully. Refer to
Figure 5
Be sure to connect the programming voltage (V
M68HC12B32EVB with the proper polarity. W8 allows V
connected to the board, but the jumper on W7 actually transfers V
the V
applies V
to maintain the voltage on the V
are not occurring. See
Refer to the Evaluation Board User’s Manual, which comes with the
M68HC12 evaluation board, Motorola part order number
M68EVB912B32, for detailed connection information.
FP
pin (pin 69) on the microcontroller. The default location of W7
DD
for connections.
Figure 5. Debugging Hardware Connections
to the V
MC68HC912B32
FP
pin, and a jumper should always be located here
Figure 6
PA1
PA0
FP
for the locations of W7 and W8.
pin when programming and erasing
RED
GREEN
(ERROR)
(OK)
FP
1 k
) source to W8 on the
Hardware Configuration
FP
Application Note
1 k
to be
FP
to
5