User’s Manual
M68HC12A4EVB Evaluation Board — Rev. 1
34
Configuration and Setup
MOTOROLA
Configuration and Setup
Some EPROM programmers do not have an editable RAM buffer capable of
holding the entire contents of U7. Instead, they program EPROMs directly from
the contents of a disk file.
If the programmer being used has an editable RAM buffer large enough to hold
the contents of U7, use procedure 1. Otherwise, to reprogram U7 from a disk
file, use procedure 2.
Procedure 1
1.
Select the Atmel Corporation’s device type AT27LV256R.
2.
Read the contents of U7 into the EPROM programmer’s editable RAM
buffer.
3.
Before modifying U7, save a copy of its contents to a disk file for backup
purposes.
4.
Change the contents of the programmer’s editable RAM buffer at
location $7ED6 from $05 to $04.
5.
Reprogram U7 with the edited contents of the programmer’s RAM
buffer.
6.
Reinstall U7 in its socket on the EVB. Be sure that its pins align with the
rightmost end of its socket, as viewed in
Figure 1-1. EVB Layout and
Component Placement
.
7.
Apply power to the EVB and press S1, the reset switch. The D-Bug12
prompt should appear on the terminal display.
8.
Ensure that the modification was performed properly by using
D-Bug12’s MD command to examine the CSSTR0 register at memory
location $003E. It should contain the value $04.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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