Engineering Bulletin

EB350

2

MOTOROLA

Hardware Setup

Setting up the A4EVB in special expanded narrow mode requires

modifying the evaluation board.

Follow these steps to make the modification:

•

When setting up the evaluation board, turn off the power to the

A4EVB.

•

Jumpers W42 and W34 should be shunted between pins 1 and 2.

W30 should be left floating or pulled out.

•

Remove the 74HC32 chip from U3.

•

Make a wire jumper from pin 2 on U3 socket to pin 3. This will

make a direct connection from the RAM-CS signal to

RAM-MSB-CS. Chip enable (CE) on pin 22 will have a direct

connection to chip select header W11.

•

Select CSP0 by shunting W11-8 between pin 2 and pin 3. CSP0

is enabled from reset and should be used to test the application

program properly.

•

Insert RAM chip in socket U6B. Notice that U6A does not have

address line 0 routed, and it is used for expanded wide mode. On

the other hand, U6B does have address line 0 routed directly and

is designed for the use of expanded narrow mode.

•

When memory paging is enabled, the EVB includes the footprint

for a 28- and 32-pin RAM footprint. Address lines 16 and 18 are

hardwired to U6B. However, address line 17 needs to be

configured via jumper header W12 by shunting pin 3 and pin 4.

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com