VSC6134
Datasheet
2.16.3.1
Motorola Pseudo-Synchronous Mode
In this mode the outbound signals from the microprocessor are referenced to the microprocessor clock.
However, the received DTACKN signal arriving at the microprocessor is assumed to be asynchronous
and is internally synchronized.
Interface
The following table lists the connections of the VSC6134 in the pseudo-synchronous mode.
Table 66. Microprocessor Interface Signals in the Motorola Pseudo-Synchronous Mode
Signal
Connection
MPU_CLK
ASN
Function
MPU_CLK
ASN_ALE
CSN
Inverted microprocessor clock
Address strobe
CSN
Chip select - Generated externally
Select Pseudo-Synchronous mode
Read/write
SYNSEL_DSN_WRN
RWN_WRN_RDN
MPMODE
MPSEL
0
RWN
1
Select synchronous mode
Select Motorola
0
DTKN_RDY
INTN
DTACKN
INTN
Data acknowledge
Interrupt
DATA[15:0]
ADDR[11:0]
DATA[15:0]
ADDR[11:0]
Microprocessor data
Microprocessor address
Read Operation
The following figure shows a flowchart of the sequence of events for a read operation.
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VMDS-10185 Revision 4.0
July 2006
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
