High-Level Data Link Control (HDLC)
15-2
Am186™CC/CH/CU Microcontrollers User’s Manual
The microcontroller uses FIFOs in both directions (16-byte transmit and 32-byte receive)
to isolate the data requests from the system bus. The controller supports SmartDMA and
programmed I/O for filling or emptying the FIFOs.
Each HDLC channel can connect to an external serial interface directly (nonmultiplexed
mode) or can pass through a time slot assigner (multiplexed mode). An HDLC channel can
connect to a raw Data Communications Equipment (DCE) interface in nonmultiplexed mode,
to a Pulse Code Modulation (PCM) highway interface in multiplexed mode, or to a General
Circuit Interface (GCI) in multiplexed mode. Each HDLC channel has the same feature set
but separate connections to its associated time slot assigner. For more information about
how the HDLC channels can be connected externally, see Chapter 16, “HDLC External
Serial Interface Configuration (TSAs)”.
The HDLC channels support full-duplex data transfer at a rate of up to 10 Mbit/s in raw DCE
and PCM Highway modes, and up to 768 Kbit/s in GCI mode (system performance may
limit total throughput). The microcontroller contains internal PCB registers for configuring
the modes of operation, controlling the HDLC channels, monitoring and reporting status,
and moving data. Each HDLC channel consists of a transmitter, a receiver, and the interface
(programmed I/O or SmartDMA).
The Am186CC microcontroller provides four HDLC channels, A through D, which support
raw DCE, PCM highway, and GCI external interfaces.
The Am186CH HDLC microcontroller provides two HDLC channels, A and B, which support
raw DCE and PCM highway external interfaces.
15.2
BLOCK DIAGRAM
Figure 15-2 shows the block diagram for a single HDLC channel, including connections
with the TSA and GCI.
CC
CH
Summary of Contents for Am186 CC
Page 1: ...Am186 CC CH CU Microcontrollers User s Manual Order 21914B...
Page 4: ...iv Am186 CC CH CU Microcontrollers User s Manual...
Page 18: ...Table of Contents xviii Am186 CC CH CU Microcontrollers User s Manual...
Page 24: ...Introduction xxiv Am186 CC CH CU Microcontrollers User s Manual...
Page 40: ...Architectural Overview 1 16 Am186 CC CH CU Microcontrollers User s Manual...
Page 86: ...System Overview 3 36 Am186 CC CH CU Microcontrollers User s Manual...
Page 92: ...Emulator Support 4 6 Am186 CC CH CU Microcontrollers User s Manual...
Page 112: ...DRAM Controller 6 8 Am186 CC CH CU Microcontrollers User s Manual...
Page 134: ...Interrupts 7 22 Am186 CC CH CU Microcontrollers User s Manual...
Page 186: ...Programmable I O Signals 9 8 Am186 CC CH CU Microcontrollers User s Manual...
Page 200: ...Watchdog Timer 11 6 Am186 CC CH CU Microcontrollers User s Manual...
Page 232: ...Asynchronous Serial Ports UARTs 13 24 Am186 CC CH CU Microcontrollers User s Manual...
Page 242: ...Synchronous Serial Port SSI 14 10 Am186 CC CH CU Microcontrollers User s Manual...
Page 264: ...High Level Data Link Control HDLC 15 22 Am186 CC CH CU Microcontrollers User s Manual...
Page 332: ...Universal Serial Bus USB 18 34 Am186 CC CH CU Microcontrollers User s Manual...
Page 348: ...Register Summary A 16 Am186 CC CH CU Microcontrollers User s Manual...
Page 376: ...Index Index 18 Am186 CC CH CU Microcontrollers User s Manual...