Retry Sequence - Motorola MC68340 User Manual

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The MC68340 retries any read or write cycle of a read-modify-write operation separately;

RMC remains asserted during the entire retry sequence. Asserting BR along with BERR

and HALT provides a relinquish and retry operation. The MC68340 does not relinquish the

bus during a read-modify-write operation. Any device that requires the MC68340 to give

up the bus and retry a bus cycle during a read-modify-write cycle must assert only BERR

and BR ( HALT must not be included). The bus error handler software should examine the

read-modify-write bit in the special status word (see Section 5 CPU32) and take the

appropriate action to resolve this type of fault when it occurs.

Freescale Semiconductor, Inc.

READ CYCLE WITH

Figure 3-19. Retry Sequence

MC68340 USER'S MANUAL

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