Kawasaki 80C152, KS152JB, 80C51 Serial Port Demand Mode, External Demand Mode

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KS152JB Universal Communications Controller Technical Specifications

during the DMA, so interrupt flags may get set, but since program execution is suspended, the interrupts will not be serviced while the DMA is in progress.

4.1.3 SERIAL PORT DEMAND MODE

In this mode the DMA can be used to service the Local Serial Channel (LSC) or the Global Serial Channel (GSC).

In Serial Port Demand Mode the DMA is initiated by any of the following conditions, if the GO bit is set:

Source Address = SBUF

.AND.

RI = 1

Destination Address = SBUF

.AND.

TI = 1

Source Address = RFIFO

.AND.

RFNE = 1

Destination Address = TFIFO

.AND.

TFNF = 1

Each time one of the above conditions is met, one DMA Cycle is executed; that is, one data byte is transferred from the source address to the destination address. On-chip hardware then clears the flag (RI, TI, RFNE, or TFNF) that initiated the DMA, and decrements BCRn. Note that since the flag that initiated the DMA is cleared, it will not generate an interrupt unless DMA servicing may be held off when alternate cycle is being used or by the status of the HOLD/HLDA logic. In these situations the interrupt for the LSC may occur before the DMA can clear the RI or TI flag. This is because the LSC is serviced according to the status of RI and TI, whether or not the DMA chan- nels are being used for the transferring of data. The GSC does not use RFNE or TFNF flags when using the DMA channels so these do not need to be disabled. When using the DMA channels to service the LSC it is recommended that the interrupts (RI and TI) be disabled. If the decremented BCRn is 0000H, on-chip hardware then clears the GO bit and sets the DONE bit. The DONE bit flags an interrupt.

4.1.4 EXTERNAL DEMAND MODE

In External Demand Mode the DMA is initiated by one of the External Interrupt pins, provided the GO bit is set. INT0 initiates a Channel 0 DMA, and INT1 initiates a Channel 1 DMA.

If the external interrupt is configured to be transition activated, then each 1-to-0 transition at the interrupt pin sets the corresponding external interrupt flag, and generates one DMA Cycle. Then, BCRn is decremented. No more DMA Cycles take place until another 1-to-0 transition is seen at the external interrupt pin. IF THE DECREMENTED bcrN = 0000H, on-chip hardware clears the GO bit and sets the DONE bit. If the external interrupt is enabled, it will be serviced.

If the external interrupt is configured to be level-activated, then DMA Cycles commence when the interrupt pin is pulled low, and continue for as long as the pin is held low and BCRn is not 0000H. If BCRn reaches 0 while the interrupt pin is still low, the GO bit is cleared, the DONE bit is set, and the DMA ceases. If the external interrupt is enabled, it will be serviced.

If the interrupt pin is pulled up before BCRn reaches 0000H, then the DMA ceases, but the GO bit

Kawasaki LSI USA, Inc.

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Ver. 0.9 KS152JB2

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Contents Introduction Technical Specifications Pin Name Alternate Function Pin DescriptionPIN Description Name Description PortXTAL2 XTAL1RST Epsen ALEPsen EbenSFR map for the cpu Special function RegistersReset Timing Reset Values of the SFRs Pcon ConfigurationsScon Sbuf Indeterminate TmodPort bit I/O Pads Port 0 I/O Pad Port 2 I/O PadPorts 4,5 Fetch via ProgramPsen Epsen CommentsTmod Timer/Counter Mode Control Register TIMER/COUNTERSMode Tcon Timer/Counter Control RegisterTimer/Counter in Mode IE Interrupt Enable Register Timer/Counter 0 in ModeInterrupts Priority Level Structure Pgste PDMA1 Pgstv PDMA0 Pgsre Pgsrv Egste EDMA1 Egstv EDMA0 Egsre EgsrvEgsrv 2BH PX0EX0 PgsrvET1 1BH PDMA1EDMA1 PT1Kawasaki LSI USA, Inc Ver .9 KS152JB2 Status of the External Pins during Idle and Power Down Power Down and IdleALE Psen Smod IDL Pcon Power Control RegisterLocal Serial Channel Controller Local Serial Port ModeSerial Port Mode Mode Load Sbuf Baud Rates Smod Timer 1 generated commonly used Baud ratesMHZ JNB SINGLE-STEP OperationReti Kawasaki LSI USA Inc Introduction Global Serial ChannelDC JAM CRC 11/IDLE CRC None11/IDLE Csma SdlcExternal clock Internal clock Control cpu Control dma Raw Receive Raw Transmit CSMA/CD Frame Format CSMA/CD OverviewPreamble BOF Address Info CRC EOF Kawasaki LSI USA, Inc Ver .9 KS152JB2 23 24 Interframe Space Jitter Tolerance CSMA/CD Data EncodingManchester Encoding BIT Time Collision DetectionMissing 0-to-1 Transition Narrow PulsesUnexpected 1-to-0 Transition Tfifo Resolution of CollisionsGSC Inactive Response to a Detected Collision What the GSC was doingDCR BackoffAlgorithm Prbs Tcdcnt Load Bkoff Slot Clock Myslot Random BackoffBKOFF= Myslot Deterministic Backoff Hardware Based Acknowledge Kawasaki LSI USA, Inc Ver .9 KS152JB2 BOF Address Control Info CRC EOF Sdlc Frame FormatKawasaki LSI USA, Inc Ver .9 KS152JB2 Nrzi BIT Time Data EncodingBIT STUFFING/STRIPPING Line Idle Sending Abort CharacterAcknowledgement Ring Network PRIMARY/SECONDARY StationsPoint-to-point Network Multi-Drop NetworkUser Defined Protocols Using a Preamble in SdlcHDLC/SDLC Comparison Sdlc HdlcPlanning for Network Changes and Expansions Line DisciplineDMA Servicing of GSC Channels Kawasaki LSI USA, Inc Ver .9 KS152JB2 Baud Rate Initialization External Driver Interface Test ModesJitter Receive Transmit Waveforms Local Value Manchester Encoding BIT TimeReceive Sampling Rate Received BIT Time ReceivedCSMA/CD Clock Recovery Receiver Clock RecoveryAddressing Determining Receiver ErrorsExternal Clocking Rcbat Crce2 CPU/DMA Control of the GSC Determining Line DisciplineCollisions and Backoff What the GSC was doing Response Successful Ending of Transmissions and Receptions GSC Register DescriptionsPL1 PL0 Length Bits GMOD84H Xtclk PL1 PL0Kawasaki LSI USA, Inc Ver .9 KS152JB2 ARB REQ Garen Xrclk Gfien IDL DCJ DCR SA5 SA4 SA3 SA2 SA1 SA0Rcabt 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 with the 80C152 DMA OperationDMA Registers SAS ISA Alternate Cycle ModeBurst Mode DAS IDAExternal Demand Mode Serial Port Demand ModeDMA Transfer from Internal Memory to Internal Memory Timing Diagrams12 OSC.PERIODS ALE Psen P1 Inst Float PCH P2 SFR DMA Cycle Resume Program ExecutionDMA Cycle 12 OSC. Periods Resume Program Execution ALE Psen 12 OSC. Periods ALE Psen Inst DMA Data OUT PCL Inst PCHDMA Cycle Resume Program Execution Arbiter Mode Request ModeHold/Hold Acknowledge ARB REQ Using the HOLD/HLDA AcknowledgeInternal Logic of the Arbiter ALE ARB If Hlda = ALE AEQ ALE REQDmxrq 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 DAS IDA SAS ISA Done Summary of DMA Control BitsInterrupt Structure IE0 ET1 EX1 ET0 EX0 TI+RIIPN1 PT1 PX1 PT0 PX0Transmit Error Flags Logic for Clearing TEN, Setting TDN GSC Transmitter Error ConditionsGSC 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 TF1 TR1 TF0 TR0 IE1 IT1 IE0 IT0 SM0 SM1 SM2 REN TB8 RB8Gate Kawasaki LSI USA, Inc 111 Ver .9 KS152JB2 DPL.7 DPL.6 DPL5 DPL.4 DPL.3 DPL.2 DPL.1 DPL.0 PortStack Pointer Data Pointer LOWDPH Timer ControlData Pointer High DPH.7 DPH.6 DPH.5 DPH.4 DPH.3 DPH.2 DPH.1 DPH.0Timer 1 LSB Timer Mode ControlGate Timer Timer 0 LSBTimer 1 MSB Timer 0 MSBSBUF.7 Serial Port ControlSM0 Serial Data BufferRS1 RS0 Program Status WordACC.7 ACC.6 ACC.5 ACC.4 ACC.3 ACC.2 ACC.1 ACC.0 AccumulatorKawasaki LSI USA, Inc 119 Ver .9 KS152JB2 Kawasaki LSI USA, Inc 120 Ver .9 KS152JB2
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