
MOTOROLA
Chapter 6. External Signals
6-7
Part III. The Hardware Interface
BADDR[27–28]
Burst address 27:28—There are five burst address output pins. These pins are outputs of the 60x
memory controller. Used in external master configuration and connected directly to the memory
devices controlled by MPC8260’s memory controller.
ALE
Address latch enable—This output pin controls the external address latch that should be used in
external master 60x bus configuration.
BCTL0
Buffer control 0—Output whose function is controlling buffers on the 60x data bus. Usually used
with BCTL1 that is multiplexed on CS10. The exact function of this pin is defined by the value of
SIUMCR[BCTLC]. See Section 4.3.2.6, “SIU Module Configuration Register (SIUMCR),” for details.
PWE[0–7]
PSDDQM[0–7]
PBS[0–7]
60x bus write enable—Outputs of the 60x bus GPCM. These pins select byte lanes for write
operations.
60x bus SDRAM DQM—The DQM pins are outputs of the SDRAM control machine. These pins
select specific byte lanes of SDRAM devices.
60x bus UPM byte select—The byte select pins are outputs of the UPM in the memory controller.
They are used to select specific byte lanes during memory operations. The timing of these pins is
programmed in the UPM. The actual driven value depends on the address and size of the
transaction and the port size of the accessed device.
PSDA10
PGPL0
60x bus SDRAM A10—(Output) from the 60x bus SDRAM controller. Part of the address when a
row address is driven and is part of the command when a column address is driven.
60x bus UPM general purpose line 0—This is one of six general purpose output lines from UPM.
The values and timing of this pin is programmed in the UPM.
PSDWE
PGPL1
60x bus SDRAM write enable—(Output) from the 60x bus SDRAM controller. Should be connected
to SDRAMs’ WE input.
60x bus UPM general purpose line 1—This is one of six general purpose output lines from UPM.
The values and timing of this pin is programmed in the UPM.
POE
PSDRAS
PGPL2
60x bus output enable—The output enable pin is an output of the 60x bus GPCM. Controls the
output buffer of memory devices during read operations.
60x bus SDRAM ras—Output from the 60x bus SDRAM controller. Should be connected to
SDRAMs’ RAS input.
60x bus UPM general purpose line 2—This is one of six general purpose output lines from UPM.
The values and timing of this pin is programmed in the UPM.
PSDCAS
PGPL3
60x bus SDRAM CAS—Output from the 60x bus SDRAM controller. Should be connected to
SDRAMs’ CAS input.
60x bus UPM general purpose line 3—This is one of six general purpose output lines from UPM.
The values and timing of this pin is programmed in the UPM.
PGTA
PUPMWAIT
PGPL4
PPBS
60x GPCM TA—This input pin is used for transaction termination during GPCM operation. Requires
external pull up resistor for proper operation.
60x bus UPM wait—This is an input to the UPM. An external device may hold this pin low to force
the UPM to wait until the device is ready for the continuation of the operation.
60x bus UPM general purpose line 4—This is one of six general purpose output lines from UPM.
The values and timing of this pin is programmed in the UPM.
60x bus parity byte select—In systems in which data parity is stored in a separate chip, this output
is used as the byte-select for that chip.
PSDAMUX
PGPL5
60x bus SDRAM address multiplexer—This output pin controls the 60x SDRAM address multiplexer
when the MPC8260 is in external master mode.
60x bus UPM general purpose line 5—This is one of six general purpose output lines from UPM.
The values and timing of this pin is programmed in the UPM.
Table 6-1. External Signals (Continued)
Signal
Description