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Parallel Interface Port (PIP)
MC68360 USER’S MANUAL
T/R—Transmit/Receive Select
This bit selects transmitter or receiver operation for the PIP when it is using the inter-
locked, pulsed, or transparent handshake modes.
0 = Data is input to the PIP.
1 = Data is output from the PIP.
7.13.7.3 PIP TIMING PARAMETERS REGISTER (PTPR). The PTPR is a 16-bit read-write
register that is cleared at reset. The PTPR holds two timing parameters, TPAR1 and TPAR2,
which are used in the pulsed handshake modes for both a PIP transmitter and a receiver.
TPAR1—Timing Parameter 1
This 8-bit value defines the number of system clocks for TPAR1 in the transmitter or re-
ceiver pulsed handshake mode. The value $00 corresponds to 1 QUICC general system
clock, and the value $FF corresponds to 256 QUICC general system clocks. A general
system clock defaults to 40 ns, assuming a 25-MHz QUICC system.
TPAR2—Timing Parameter 2
This 8-bit value defines the number of system clocks for TPAR2 in the transmitter or re-
ceiver pulsed handshake mode. The value $00 corresponds to 1 QUICC general system
clock, and the value $FF corresponds to 256 QUICC general system clocks. A general
system clock defaults to 40 ns, assuming a 25-MHz QUICC system.
7.13.7.4 PIP BUFFER DESCRIPTORS. BDs for the receiver and transmitter that support
PIP operation were still in preparation at the time of writing.
7.13.7.5 PIP EVENT REGISTER (PIPE). The PIPE is an 8-bit register used to report events
recognized by the PIP and to generate interrupts. It shares the same address as the SMC2
event register; thus, SMC2 cannot be used simultaneously with the PIP. Upon recognition
of an event, the PIP sets its corresponding bit in the PIPE. Interrupts generated by this reg-
ister may be masked in the PIP mask register.
The PIPE is a memory-mapped register that may be read at any time. A bit is cleared by
writing a one (writing a zero does not affect a bit’s value). More than one bit may be cleared
at a time. All unmasked bits must be cleared before the CP will clear the internal interrupt
request. This register is cleared at reset.
Bits 7–4—Reserved
CCR—Control Character Received
A control character was received (with reject (R) = 1) and stored in the receive control
character register.
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9876543210
TPAR2
TPAR1
76543210
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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