External Signals
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
6-4 Freescale Semiconductor
DBB
IRQ3
60x data bus busy—(Input/output) As an output the PowerQUICC II asserts this pin for the
duration of the data bus tenure. Following a TA, which terminates the data bus tenure, the
PowerQUICC II negates DBB for a fraction of a bus cycle and than stops driving this pin. As an
input, the PowerQUICC II does not assume 60x data bus ownership as long as it senses DBB
asserted by an external 60x bus master.
Interrupt request 3—This input is one of the eight external lines that can request (by means of the
internal interrupt controller) a service routine from the core.
D[0–63] 60x data bus—These are input/output pins. In write transactions the 60x bus master drives the
valid data on this bus. In read transactions the 60x slave drives the valid data on this bus.
DP[0]
RSRV
EXT_BR2
60x data parity 0—(Input/output) The 60x agent that drives the data bus drives also the data parity
signals. The value driven on data parity 0 pin should give odd parity (odd number of 1’s) on the
group of signals that includes data parity 0 and D[0–7].
Reservation—The value driven on this output pin represents the state of the coherency bit in the
reservation address register that is used by the lwarx and stwcx. instructions.
External bus request 2—(Input). An external master should assert this pin to request 60x bus
ownership from the internal arbiter.
IRQ1
DP[1]
EXT_BG2
Interrupt request 1—This input is one of the eight external lines that can request (by means of the
internal interrupt controller) a service routine from the core.
60x data parity 1—(Input/output) The 60x agent that drives the data bus drives also the data parity
signals. The value driven on data parity 1 pin should give odd parity (odd number of ‘1’s) on the
group of signals that includes data parity 1 and D[8–15].
External bus grant 2—(Output) The PowerQUICC II asserts this pin to grant 60x bus ownership
to an external bus master.
IRQ2
DP[2]
TLBISYNC
EXT_DBG2
Interrupt request 2—This input is one of the eight external lines that can request (by means of the
internal interrupt controller) a service routine from the core.
60x data parity 2—(Input/output) The 60x agent that drives the data bus drives also the data parity
signals. The value driven on data parity 2 pin should give odd parity (odd number of ‘1’s) on the
group of signals that includes data parity 2 and S[16–23].
TLB sync—This input pin can be used to synchronize 60x core instruction execution to hardware
indications. Asserting this pin will force the core to stop instruction execution following a tlbsync
instruction execution. The core resumes instructions execution once this pin is negated.
External data bus grant 2—(Output) The PowerQUICC II asserts this pin to grant 60x data bus
ownership to an exter nal bus master.
Table6-1. External Signals (continued)
Signal Description