Motorola MPC8260 - Manual (Page 975)

MOTOROLA Chapter 35. Parallel I/O Ports 35-19
Part IV. Communications Processor Module
35.6 Interrupts from Port C
The port C lines associated with CDx and CTSx have a mode of operation where the pin
can be internally connected to the SCC/FCC but can also generate interrupts. Port C still
detects changes on the CTS and CD pins and asserts the corresponding interrupt request,
but the SCC/FCC simultaneously uses CTS and/or CD to automatically control operation.
This lets the user fully implement protocols V.24, X.21, and X.21 bis (with the assistance
of other general-purpose I/O lines).
To conÞgure a port C pin as a CTS or CD pin that connects to the SCC/FCC and generates
interrupts, these steps should be followed:
1. Write the corresponding PPARC bit with a 1 and PSORC bit with 0.
2. Write the corresponding PDIRC bit with a zero.
3. Set the SIEXR bit (in the interrupt controller) to determine which edges cause
interrupts.
PD8 FCC2: TxPrty
UTOPIA
SMC1: SMRXD GND BRG5: BRGO
PD7 SMC1: SMSYN GND FCC1: TxAddr[3] 1
MPHY, master,
multiplexed polling
FCC2: TxAddr[4]
MPHY, master,
multiplexed polling
FCC1: TxAddr[3] 2
MPHY, slave,
multiplexed polling
FCC1: TxClav2 2
MPHY, master, direct
polling
FCC2: TxAddr[1]
MPHY, slave,
multiplexed polling
GND
PD6 FCC1: TxD[4]
UTOPIA 16
IDMA1: DACK
PD5 FCC1: TxD[3]
UTOPIA 16
IDMA1: DONE 3
Inout
(secondary option)
V
DD
PD4 BRG8: BRGO TDM_D1: L1TSYNC/
GRANT 3
(secondary option)
GND FCC3: RTS SMC2: SMRXD 3
(secondary option)
GND
1 MPHY address pins 3 and 4 (master mode) can come from FCC2, depending on CMXUAR programming. (See
Section 15.4.1, ÒCMX UTOPIA Address Register (CMXUAR).Ó)
2 MPHY address pins 0Ð4 (slave mode) can come from FCC2, depending on CMXUAR programming. (See
Section 15.4.1, ÒCMX UTOPIA Address Register (CMXUAR).Ó)
3 Available only when the primary option for this function is not used.
Table 35-8. Port D Dedicated Pin Assignment (PPARD = 1) (Continued)
Pin
Pin Function
PSORD = 0 PSORD = 1
PDIRD = 1 (Output) PDIRD = 0 (Input)
Default
Input
PDIRD = 1 (Output)
PDIRD = 0 (Input, or
Inout if SpeciÞed)
Default
Input