Kawasaki KS152JB HDLC/SDLC Comparison, Sdlc Hdlc, Using a Preamble in Sdlc, User Defined Protocols

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KS152JB Universal Communications Controller Technical Specifications

3.3.9 HDLC/SDLC COMPARISON

HDLC (High level Data Link Control) is a standard adopted by the International Standards Orga- nization (ISO). The HDLC standard is defined in the ISO document # ISO6159 -HDLC unbal- anced classes of procedure. IBM developed the SDLC protocol as a subset of HDLC. SDLC confirms to HDLC protocol requirements, but is more restrictive. SDLC contains a more precise definition on the modes of operation.

Some of the major differences between SDLC and HDLC are:

SDLC

HDLC

Unbalanced (primary/secondary)

Balanced (peer to peer)

Modulo 8(no extensions allowed,

Modulo 128 (up to 127 outstanding frames before

acknowledge is required)

 

up to 7 out-standing frames before

 

acknowledge is required)

 

8-bit addressing only

Extended addressing

Byte aligned data

Variable size of data

The C152 does not support HDLC implementation requiring data alignment other than byte align- ment. The user will find that many of the protocol parameters are programmable in the C152 which allows easy implementation of proprietary or standard HDLC network. User software needs to implement the control field functions.

3.3.10 USING A PREAMBLE IN SDLC

When transmitting a preamble in SDLC mode, the user should be aware that the pattern of 10101010.....is output. NRZI encoding is used in SDLC when the internal baud rate generator is

the clock source and this means that a transition will occur every two bit times, when a 0 is trans- mitted. This compares with some others SDLC devices, most of which transmit the pattern 00000000..... which will cause a transition every bit time. Our past experience has shown that the

C152 preamble does not cause a problem with most other devices. This is because the preamble is used only to define the relative bit time boundaries within some variation allowed by the receiving station, and the C152 does not have any problems with receiving a preamble consisting of all 0s. One note of caution however. If idle fill flags are used in conjunction with a preamble, the address 00(00)H and 55(55) H should not be assigned to any C152 as the preamble following the idle fill flags will be interpreted as an address.

3.4 User Defined Protocols

The explanation on the implementation of user defined protocols would go beyond the scope of this manual, but examining Table 3.1 should give the reader a consolidated list of most of the pos- sibilities. In this manual, any deviation from the documents that cover the implementation of CSMA/CD or SDLC are considered user defined protocols. Examples of this would be the use of SDLC with the 32-bit CRC selected or CSMA/CD with hardware based acknowledge.

Kawasaki LSI USA, Inc.

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Ver. 0.9 KS152JB2

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Contents Introduction Technical Specifications Name Description Port Pin DescriptionPIN Description Pin Name Alternate FunctionXTAL1 XTAL2RST Eben ALEPsen EpsenSpecial function Registers SFR map for the cpuReset Timing Reset Values of the SFRs Sbuf Indeterminate Tmod ConfigurationsScon PconPort 0 I/O Pad Port 2 I/O Pad Port bit I/O PadsPorts 4,5 Comments ProgramPsen Epsen Fetch viaTIMER/COUNTERS Tmod Timer/Counter Mode Control RegisterTcon Timer/Counter Control Register ModeTimer/Counter in Mode Timer/Counter 0 in Mode IE Interrupt Enable RegisterInterrupts Priority Level Structure Egste EDMA1 Egstv EDMA0 Egsre Egsrv Pgste PDMA1 Pgstv PDMA0 Pgsre PgsrvPgsrv PX0EX0 Egsrv 2BHPT1 PDMA1EDMA1 ET1 1BHKawasaki LSI USA, Inc Ver .9 KS152JB2 Power Down and Idle Status of the External Pins during Idle and Power DownALE Psen Pcon Power Control Register Smod IDLLocal Serial Channel Local Serial Port Mode ControllerSerial Port Mode Mode Load Sbuf Baud Rates Timer 1 generated commonly used Baud rates SmodMHZ SINGLE-STEP Operation JNBReti Kawasaki LSI USA Inc Global Serial Channel Introduction11/IDLE CRC None DC JAM CRCCsma Sdlc 11/IDLEExternal clock Internal clock Control cpu Control dma Raw Receive Raw Transmit CSMA/CD Overview CSMA/CD Frame FormatPreamble BOF Address Info CRC EOF Kawasaki LSI USA, Inc Ver .9 KS152JB2 23 24 Interframe Space Collision Detection CSMA/CD Data EncodingManchester Encoding BIT Time Jitter ToleranceNarrow Pulses Missing 0-to-1 TransitionUnexpected 1-to-0 Transition Response to a Detected Collision What the GSC was doing Resolution of CollisionsGSC Inactive TfifoBackoff DCRAlgorithm Random Backoff Prbs Tcdcnt Load Bkoff Slot Clock MyslotBKOFF= Myslot Deterministic Backoff Hardware Based Acknowledge Kawasaki LSI USA, Inc Ver .9 KS152JB2 Sdlc Frame Format BOF Address Control Info CRC EOFKawasaki LSI USA, Inc Ver .9 KS152JB2 Data Encoding Nrzi BIT TimeBIT STUFFING/STRIPPING Sending Abort Character Line IdleAcknowledgement Multi-Drop Network PRIMARY/SECONDARY StationsPoint-to-point Network Ring NetworkSdlc Hdlc Using a Preamble in SdlcHDLC/SDLC Comparison User Defined ProtocolsLine Discipline Planning for Network Changes and ExpansionsDMA Servicing of GSC Channels Kawasaki LSI USA, Inc Ver .9 KS152JB2 Baud Rate Initialization Test Modes External Driver InterfaceJitter Receive BIT Time Received Local Value Manchester Encoding BIT TimeReceive Sampling Rate Received Transmit WaveformsReceiver Clock Recovery CSMA/CD Clock RecoveryRcbat Crce Determining Receiver ErrorsExternal Clocking AddressingDetermining Line Discipline 2 CPU/DMA Control of the GSCCollisions and Backoff What the GSC was doing Response GSC Register Descriptions Successful Ending of Transmissions and ReceptionsGMOD84H Xtclk PL1 PL0 PL1 PL0 Length BitsKawasaki LSI USA, Inc Ver .9 KS152JB2 DCJ DCR SA5 SA4 SA3 SA2 SA1 SA0 ARB REQ Garen Xrclk Gfien IDLRcabt Crce RDN Rfne Gren Haben Kawasaki LSI USA, Inc Ver .9 KS152JB2 LNI Noack Tcdt TDN Tfnf TEN DMA Kawasaki LSI USA, Inc Ver .9 KS152JB2 DMA Operation DMA with the 80C152DMA Registers DAS IDA Alternate Cycle ModeBurst Mode SAS ISASerial Port Demand Mode External Demand ModePCH P2 SFR DMA Cycle Resume Program Execution Timing Diagrams12 OSC.PERIODS ALE Psen P1 Inst Float DMA Transfer from Internal Memory to Internal Memory12 OSC. Periods ALE Psen Inst DMA Data OUT PCL Inst PCH DMA Cycle 12 OSC. Periods Resume Program Execution ALE PsenDMA Cycle Resume Program Execution Request Mode Arbiter ModeHold/Hold Acknowledge Using the HOLD/HLDA Acknowledge ARB REQALE ARB If Hlda = ALE AEQ ALE REQ Internal Logic of the ArbiterDmxrq Internal Logic of the Requester DMA Arbitration Kawasaki LSI USA, Inc.oup, Inc Ver .9 KS152JB2 Kawasaki LSI USA, Inc Ver .9 KS152JB2 Kawasaki LSI USA, Inc Ver .9 KS152JB2 DMA Arbitration with Hold/Hold Ack Summary of DMA Control Bits DAS IDA SAS ISA DoneInterrupt Structure IE0 TI+RI ET1 EX1 ET0 EX0PT1 PX1 PT0 PX0 IPN1GSC Transmitter Error Conditions Transmit Error Flags Logic for Clearing TEN, Setting TDNGSC Receiver Error Conditions Glossary Kawasaki LSI USA, Inc Ver .9 KS152JB2 DCON0/1 092H,093H Xtclk PL1 PL0 Kawasaki LSI USA, Inc 102 Ver .9 KS152JB2 Kawasaki LSI USA, Inc 103 Ver .9 KS152JB2 PT1 PX1 PT0 EX0 Myslot 0F5H DCJ DCR SA5 SA4 SA3 SA2 SA1 SA0 Smod ARB REQ Garen Xrclk Gfien IDL OVR Rcabt Crce RDN Rfne Gren Haben Kawasaki LSI USA, Inc 108 Ver .9 KS152JB2 SM0 SM1 SM2 REN TB8 RB8 TF1 TR1 TF0 TR0 IE1 IT1 IE0 IT0Gate Kawasaki LSI USA, Inc 111 Ver .9 KS152JB2 Data Pointer LOW PortStack Pointer DPL.7 DPL.6 DPL5 DPL.4 DPL.3 DPL.2 DPL.1 DPL.0DPH.7 DPH.6 DPH.5 DPH.4 DPH.3 DPH.2 DPH.1 DPH.0 Timer ControlData Pointer High DPHTimer 0 LSB Timer Mode ControlGate Timer Timer 1 LSBTimer 0 MSB Timer 1 MSBSerial Data Buffer Serial Port ControlSM0 SBUF.7Program Status Word RS1 RS0Accumulator ACC.7 ACC.6 ACC.5 ACC.4 ACC.3 ACC.2 ACC.1 ACC.0Kawasaki LSI USA, Inc 119 Ver .9 KS152JB2 Kawasaki LSI USA, Inc 120 Ver .9 KS152JB2