Motorola MC68340 User Manual

MOTOROLA

3- 39

asserted, the A31–A0, FCx, SIZx, and R/

W

 signals are again driven to their previous

states. The MC68340 does not service interrupt requests while it is halted.

 

CLKOUT

S0

S2

S4

R/W

AS

DS

HALT

S0

S2

S4

BR

BG

BGACK

S0

READ

HALT

(ARBITRATION PERMITTED

WHILE THE PROCESSOR IS

HALTED)

READ

DSACKx

A31–A0

FC3–FC0

D15–D10

A double bus fault results when a bus error or an address error occurs during the
exception processing sequence for any of the following:

• A previous bus error

• A previous address error

• A reset

For example, the MC68340 attempts to stack several words containing information about
the state of the machine while processing a bus error exception. If a bus error exception

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Freescale Semiconductor, Inc.

For More Information On This Product,

   Go to: www.freescale.com

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