Kawasaki KS152JB, 80C152, 80C51 technical specifications DMA Arbitration with Hold/Hold Ack

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KS152JB Universal Communications Controller Technical Specifications

decides it wants to do Burst mode DMA. The sequence of events might be:

Instruction cycle (sets GO bit in DCON1) Instruction cycle (during which TFNF gets set) DMA0 cycle

DMA1 cycle DMA1 cycle DMA1 cycle

......

DMA1 cycle (completes channel 1 burst) Instruction cycle

DMA0 cycle Instruction cycle

...........

This sequence begins with two Instruction cycles. The ﬁrst one accesses a DMA register (DCON1), and therefore is followed by another Instruction cycle, which presumably does not access a DMA register. After the second Instruction cycle both channels are ready to generate DMA cycles, and channel 0 of course takes precedence. After the DM0 cycle, channel 0 must wait for an Instruction cycle before it can access TFIFO again. Channel 1, being in Burst mode, doesn’t have that restriction, and is therefore granted a DMA1 cycle. After the ﬁrst DMA1 cycle, channel 0 is still waiting for an Instruction cycle and channel 1 still does not have that restriction. There follows another DMA1 cycle.

The result is that in this particular case channel 0 has to wait until channel 1 completes its Burst mode DMA, and then has to wait for an Instruction cycle to be generated, before it can continue its own DMA to TFIFO. The delay in servicing TFFIO can cause an Underﬂow condition in the GSC transmission.

The delay will not occur if channel 1 is conﬁgured to Alternate Cycles mode, since channel 0 would then see the Instruction cycles it needs to complete its logic requirements for asserting its request.

4.4.1 DMA Arbitration with Hold/Hold Ack

The Hold/Hold Acknowledge feature is invoked by setting either the ARB or REQ bit in PCON. Their effect is to add the requirements of the Hold/Hold Ack protocol to mode_logic ( ). This amounts to replacing every expression “return 1” in with the expression “return hld_hlda_logic ( ) “, where hld_hlda_logic ( ) is a function which returns 1 if the Hold/Hold Ack protocol is satis- ﬁed, and returns 0 otherwise. A suitable deﬁnition for hld_hlda_logic () is shown in Figure 4.14.

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