MC68HC711xxxx Motorola, MC68HC711xxxx Datasheet - Page 234

• Manufacturer Part Number: MC68HC711xxxx
• Description: Microcontrollers
• Manufacturer: Motorola

Application Note
Driving Boot Mode from a Personal Computer
Hardware
Software
234
In this example, a personal computer is used as the host to drive the
bootloader of an MC68HC711E9. An M68HC11 EVBU is used for the
target MC68HC711E9. A large program is transferred from the personal
computer into the EPROM of the target MC68HC711E9.
Figure 7
12-volt (nominal) EPROM programming voltage. The XIRQ pin is
connected to a pullup resistor, two jumpers, and the 60-pin connectors,
P4 and P5. The object of the modification is to isolate the XIRQ pin and
then connect it to the programming power supply. Carefully cut the trace
on the solder side of the EVBU as indicated in
disconnects the pullup resistor RN1 D from XIRQ but leaves P4–18,
P5–18, and jumpers J7 and J14 connected so the EVBU can still be
used for other purposes after programming is done. Remove any
fabricated jumpers from J7 and J14. The EVBU normally has a jumper
at J7 to support the trace function
Figure 8
EVBU. The 3-terminal jumper allows the XIRQ line to be connected to
either the programming power supply or to a substitute pullup resistor for
XIRQ. The 100-ohm resistor is a current limiter to protect the 12-volt
input of the MCU. The resistor and LED connected to P5 pin 9 (port C
bit 0) is an optional indicator that lights when programming is complete.
BASIC was chosen as the programming language due to its readability
and availability in parallel versions on both the IBM
Macintosh
techniques for use with an M68HC11 and is not necessarily intended to
be a finished, commercial program. For example, there is little error
checking, and the user interface is elementary. A complete listing of the
BASIC program is included in
Computer
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Macintosh is a registered trademark of Apple Computers, Inc.
IBM is a registered trademark of International Business Machines.
shows a small circuit that is added to the wire-wrap area of the
shows a small modification to the EVBU to accommodate the

with moderate comments. The following paragraphs include
. The program demonstrates several programming
Listing 2. BASIC Program for Personal
Figure
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PC and the
7. This
AN1060 — Rev. 1.0
MOTOROLA