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MPC106 PCIB/MC User's Manual
MOTOROLA
2.2.4.18 SDRAM Internal Bank Select (SDBA0)—Output
The SDRAM internal bank select (SDBA0) signal is an output signal on the MPC106.
Following are the state meaning and timing comments for the SDBA0 output signal.
State Meaning
Asserted/Negated—Selects the SDRAM internal bank
(Low = bank A, High = bank B) to be activated during the row
address phase and selects the SDRAM internal bank for the read or
write operation during the column address phase of the memory
access.
Timing Comments
Assertion/Negation—The same as SDMA[1–11].
2.2.4.19 SDRAM Column Address Strobe (SDCAS)—Output
The SDRAM column address strobe (SDCAS) signal is an output on the MPC106.
Following are the state meaning and timing comments for the SDCAS output signal.
State Meaning
Asserted—SDCAS is part of the SDRAM command encoding and is
used for SDRAM column selection during read or write operations.
See Section 6.4, “SDRAM Interface Operation,” for more
information.
Negated—SDCAS is part of SDRAM command encoding used for
SDRAM column selection during read or write operations.
Timing Comments
Assertion—For SDRAM, SDCAS is valid on the rising edge of the
60x bus clock when a CS
n
signal is asserted.
2.2.4.20 SDRAM Address (SDMA[1–11])—Output
The SDRAM address (SDMA[1–11]) signals consist of 11 output signals on the MPC106.
Following are the state meaning and timing comments for the SDMA[1–11] output signals.
State Meaning
Asserted/Negated—Represents the row/column multiplexed
physical address for SDRAMs (SDMA1 is the most-significant
address bit; SDMA11 is the least-significant address bit).
Timing Comments
Assertion/Negation—For SDRAM, the row address is valid on the
rising edge of the 60x bus clock when SDRAS is asserted, and the
column address is valid on the rising edge of the 60x bus clock when
SDCAS is asserted.
2.2.4.21 SDRAM Row Address Strobe (SDRAS)—Output
The SDRAM row address strobe (SDRAS) signal is an output on the MPC106. Following
are the state meaning and timing comments for the SDRAS output signal.
State Meaning
Asserted/Negated—SDRAS is part of the SDRAM command
encoding and is used for SDRAM bank selection during read or write
operations. See Section 6.4, “SDRAM Interface Operation,” for
more information.