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MPC106 PCIB/MC User's Manual
MOTOROLA
2.2.3.1.1 Address Strobe (ADS)—Output
The address strobe (ADS) signal is an output on the MPC106. It is used for burst SRAM
configurations only. Asynchronous SRAM configurations use the alternate function DALE.
Following are the state meaning and timing comments for the ADS signal. Note that this
signal has an on-chip pull-up resistor.
State Meaning
Asserted—Indicates that the address is valid to be latched by the
burst SRAMs.
Negated—Indicates that the burst SRAMs should use addresses from
their internal counters.
Timing Comments
Assertion—The MPC106 asserts ADS during the 60x bus address
phase. The MPC106 also asserts ADS when a write cycle needs to be
aborted.
Negation—The MPC106 negates ADS until the data access is
completed.
2.2.3.1.2 Burst Address 0 (BA0)—Output
The burst address 0 (BA0) signal is an output on the MPC106. It is used for asynchronous
SRAM configurations only. Following are the state meaning and timing comments for the
BA0 signal.
State Meaning
Asserted/Negated—Indicates the most-significant bit of the burst
counter address.
Timing Comments
Assertion/Negation—Valid when DALE is negated, after each TA
assertion.
2.2.3.1.3 Burst Address 1 (BA1)—Output
The burst address 1 (BA1) signal is an output on the MPC106. It is used for asynchronous
SRAM configurations only. Burst SRAM configurations use the alternate function BAA.
Following are the state meaning and timing comments for the BA1 signal.
State Meaning
Asserted/Negated—Indicates the least-significant bit (lsb) of the
burst counter address.
Timing Comments
Assertion/Negation—Valid when DALE is negated, after each TA
assertion.
2.2.3.1.4 Bus Address Advance (BAA)—Output
The bus address advance (BAA) signal is an output on the MPC106. It is used for burst
SRAM configurations only. Asynchronous SRAM configurations use the alternate function
BA1. Following are the state meaning and timing comments for the BAA signal.
State Meaning
Asserted—Indicates that the burst SRAMs should increment their
internal addresses.
Negated—Indicates no change to the addresses.