MC68LC302 Datasheet, PDF (109/169 Pages) Motorola, Inc – Low Power Integrated Multiprotocol Processor Reference Manual

Signal Description
5.11 PHYSICAL LAYER SERIAL INTERFACE PINS
The physical layer serial interface has 18 pins, and all of them have multiple functions. The
pins can be used in a variety of configurations in ISDN or non-ISDN environments. Table 5-
4 shows the functionality of each group of pins and their internal connection to the two SCCs
and one SCP controllers. The physical layer serial interface can be configured for non-mul-
tiplexed operation (NMSI) or multiplexed operation that includes IDL, GCI, and PCM high-
way modes. IDL and GCI are ISDN interfaces. When working in one of the multiplexed
modes, the NMSI1/ISDN physical interface can be connected to both SCC controllers.
Table 5-5. Serial Interface Pin Functions
First Function
NMSI1 (7)
NMSI2 (8)
PAIO/SCP (3)
Connected To
SCC1 Controller
SCC2 Controller
SCP Controller
Second Function
ISDN Interface
PIO—Port A
PIO—Port A
Connected To
SCC1/SCC2
Parallel I/O
Parallel I/O
NOTE: Each one of the parallel I/O pins can be configured individually.
5.12 TYPICAL SERIAL INTERFACE PIN CONFIGURATIONS
Table 5-5 shows typical configurations of the physical layer interface pins for an ISDN envi-
ronment. Table 5-7 shows potential configurations of the physical layer interface pins for a
non-ISDN environment. The timer pins can be used in all applications either as dedicated
functions or as PIO pins.
Table 5-6. Example ISDN Configuration
Pins
NMSI1 or ISDN I/F
PAIO or SCP
Connected To
SCC1 and SCC2
PA12–PA8
SCP
Used As
SCC1 Used as ISDN D-ch
SCC2 Used as ISDN B-ch
PIO
or
Status/Control Exchange
NOTES:
1. ISDN environment with SCP port for status/control exchange and with
existing terminal (for rate adaption).
2. D-ch is used for signaling.
3. B-ch is used for voice (external CODEC required) or for data transfer.
Table 5-7. Typical Generic Configurations
Pins
NMSI1 or ISDN I/F
NMSI2
PAIO/SCP
Connected To
SCC1
SCC2
SCP
Used As
Terminal with Modem
Terminal with Modem
Status/Control Exchange
NOTE: Generic environment with two SCC ports (any protocol) and the SCP port.
5.13 NMSI1 OR ISDN INTERFACE PINS
The NMSI1 or ISDN interface pins are shown in Figure 5-9.
5-14
MC68LC302 REFERENCE MANUAL
MOTOROLA