Am186™CC/CH/CU Microcontrollers User’s Manual
16-1
CHAPTER
16
HDLC EXTERNAL SERIAL
INTERFACE CONFIGURATION (TSAS)
Note: Only the Am186CC and Am186CH microcontrollers support the TSAs.
16.1
OVERVIEW
Time Slot Assigners (TSAs) and muxing logic between the HDLC channels and the external
communications interfaces of the chip provide flexible data path control on the Am186CC
and Am186CH microcontrollers. This data path control, combined with flexible time slot
allocation, allows the microcontroller’s external data streams to take on a wide variety of
forms.
The Am186CC microcontroller supports raw DCE, PCM Highway, and General Circuit
Interface (GCI) external data streams.
The Am186CH HDLC microcontroller supports raw DCE and PCM Highway external data
streams.
In the Am186CC microcontroller, interface A not only allows for a dedicated DCE/PCM
HDLC path, but has the capability to multiplex GCI/PCM data from each of the remaining
nondedicated HDLC channels.
Depending on the application, each HDLC can communicate to the external world with or
without a TSA. Each TSA resides between a PCM Highway internal bus and an individual
HDLC channel. A TSA’s main function is to allow the transmission and reception of data to
and from an individual HDLC by providing the appropriate HDLC clock and clock enable
signals during its programmed time slot within an 8-KHz frame.
In
nonmultiplexed mode (there is no time-division multiplexing), an individual external serial
bus interface connects directly to an individual HDLC for both transmission and reception.
Configuring the microcontroller’s muxing logic for a specific raw DCE data path uses
nonmultiplexed mode.
In
multiplexed mode (there is time-division multiplexing), all HDLC data that enters or leaves
the microcontroller passes through a TSA. Configuring the microcontroller’s muxing logic
and TSAs for the multiplexed PCM Highway uses multiplexed mode. External interface A
is unique in that it allows multiple time slots, to and from each HDLC, to multiplex on and
off this single interface.
Configuring the Am186CC microcontroller’s muxing logic and TSAs for the GCI data path
also uses multiplexed mode.
Time Slot selection allows up to 156 8-bit time slots within a time-division multiplexed (TDM)
frame. Each TSA channel can support a burst data rate to or from the HDLC of up to 10
Mbit/s in DCE and PCM highway modes. In all modes of operation, each channel is capable
of supporting full-duplex communications. With a maximum data rate of 10 Mbit/s and an
8-KHz frame, each channel provides programmability to support a maximum of 156 time
slots per TDM frame. (Although the microcontroller supports up to 4096 bit positions, this
requires a lower frame synchronization (frame sync) or a higher, unguaranteed clock rate.)
CH
CC
CC
CH
CC
CC
Содержание Am186 CC
Страница 1: ...Am186 CC CH CU Microcontrollers User s Manual Order 21914B...
Страница 4: ...iv Am186 CC CH CU Microcontrollers User s Manual...
Страница 18: ...Table of Contents xviii Am186 CC CH CU Microcontrollers User s Manual...
Страница 24: ...Introduction xxiv Am186 CC CH CU Microcontrollers User s Manual...
Страница 39: ...Architectural Overview Am186 CC CH CU Microcontrollers User s Manual 1 15 Figure 1 6 32 Channel Linecard CH CC...
Страница 40: ...Architectural Overview 1 16 Am186 CC CH CU Microcontrollers User s Manual...
Страница 86: ...System Overview 3 36 Am186 CC CH CU Microcontrollers User s Manual...
Страница 92: ...Emulator Support 4 6 Am186 CC CH CU Microcontrollers User s Manual...
Страница 112: ...DRAM Controller 6 8 Am186 CC CH CU Microcontrollers User s Manual...
Страница 134: ...Interrupts 7 22 Am186 CC CH CU Microcontrollers User s Manual...
Страница 186: ...Programmable I O Signals 9 8 Am186 CC CH CU Microcontrollers User s Manual...
Страница 200: ...Watchdog Timer 11 6 Am186 CC CH CU Microcontrollers User s Manual...
Страница 232: ...Asynchronous Serial Ports UARTs 13 24 Am186 CC CH CU Microcontrollers User s Manual...
Страница 242: ...Synchronous Serial Port SSI 14 10 Am186 CC CH CU Microcontrollers User s Manual...
Страница 264: ...High Level Data Link Control HDLC 15 22 Am186 CC CH CU Microcontrollers User s Manual...
Страница 332: ...Universal Serial Bus USB 18 34 Am186 CC CH CU Microcontrollers User s Manual...
Страница 348: ...Register Summary A 16 Am186 CC CH CU Microcontrollers User s Manual...
Страница 376: ...Index Index 18 Am186 CC CH CU Microcontrollers User s Manual...