Parallel Interface Port (PIP)
7-340
MC68360 USER’S MANUAL
When T/R = 1 (PIP is a transmitter), the definition is as follows:
0 = Ignore the BUSY signal input on PB0 for the transmitter.
1 = Assertion of STB is conditioned by BUSY is negation. STB will not be asserted until
the BUSY signal, input on PB0, is negated. EBSY will only take effect if bit 0 of PB-
PAR is 0 to configure this pin to belong to the PIP and bit 0 of PBDIR is 0 to make
this pin an input.
NOTE
The programming of MODL has no effect on the BUSY pin if
EBSY is set.
TMOD—Timing Mode (Centronics Receiver)
These bits are only valid when T/R is set to receive and MODH is set to pulsed handshake
mode. Otherwise they are ignored.
00 = Centronics receiver timing mode 0 (BUSY is negated before ACK is asserted).
01 = Centronics receiver timing mode 1 (BUSY is negated after ACK assertion but be-
fore ACK negation).
10 = Centronics receiver timing mode 2 (BUSY is negated after ACK negation).
11 = Centronics receiver timing mode 3 (BUSY is negated by host software).
MODL—Mode Low
These bits determine the mode of the PIP’s lower 8 pins (PB7–PB0).
00 = Port B general-purpose I/O mode (under host control).
01 = Transparent handshake mode (under RISC or host control).
1x = Mode of operation is controlled by MODH.
NOTE
The BUSY pin (PB0) is not affected by MODL programming if
EBSY is set.
MODH—Mode High
These bits determine the mode of the PIP’s upper 10 pins (PB17–PB8). MODH may be
changed when the RISC processor is not currently receiving or transmitting data.
00 = Port B general-purpose I/O (under host control).
01 = Transparent handshake mode (under RISC or host control).
10 = Interlocked handshake mode (under RISC or host control).
11 = Pulsed handshake mode (under RISC or host control).
HSC—Host Control
0 = The PIP data transfers are controlled by the RISC in the CPM, using the PIP pa-
rameter RAM, BDs, and SDMA channels.
1 = The PIP data transfers are controlled by the host software (i.e., CPU32+ or other
external processor in the system).
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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