Kawasaki 80C152, KS152JB, 80C51 technical specifications Baud Rate

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KS152JB Universal Communications Controller Technical Specifications

this same DMA bit.

The interrupts EGSTE (IEN1.5), GSC transmit error; EGSTV (IEN1.3), GSC transmit valid; EGSRE (IEN1.1), GSC receive error; and EGSRV (IEN1.0), GSC receive valid; need to be enabled. The DMA interrupts are normally not used when servicing the GSC with the DMA chan- nels. To ensure that the DMA interrupts are normally not used when servicing the GSC with the DMA channels. To ensure that the DMA interrupts are not responded to is a function of the user software and should be checked by the software to make sure they are not enabled. priority for these interrupts can also be set at this time. Whether to use high or low priority needs to be decided by the user. When responding to the GSC interrupts, if a buffer is being used to store the GSC information, then the DMA registers used for the buffer will probably need updating.

After this initialization, all that needs to be done when the GSC is actually going to be used is: load the byte count, set-up the source addresses for the DMA channel servicing the transmitter, set-up the destination addresses for the DMA channel servicing the receiver, and start the DMA transfer. The GSC enable bits should be set first and then the GO bits for the DMA. This initiates the data transfers.

This simplifies the maintenance of the GSC and can make the implementation of an external buffer for packetized information automatic.

An external buffer can be used as the source of data for transmission, or the destination of data from the receiver. In this arrangement, the message size is limited to the RAM size or 64K, which- ever is smaller. By using an external buffer, the data can be accessed by other devices which may want access to the serial data. The amount of time required for the external data moves will also decrease. Under CPU control, a “MOVX” command would take 24 oscillator periods to complete.

Under DMA control, external to internal, or internal to external, data moves take only 12 oscilla- tor periods.

3.5.4 BAUD RATE

The GSC baud rate is determined by the contents of the SFR, BAUD, or the external clock. The formula used to determine the baud rate when using the internal clock is:

(fosc)/ ((BAUD +1)*8)

For example if a 12 MHz oscillator is used the baud rate can vary from:

12,000,000/ ((0+1)*8) = 1.5 MBPS

to:

12,000,000/((255+1)*8) = 5.859 KBPS

There are certain requirements that the external clock will need to meet. These requirements are

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 FunctionXTAL2 XTAL1RST 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 IE Interrupt Enable Register Timer/Counter 0 in ModeInterrupts 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 Status of the External Pins during Idle and Power Down Power Down and IdleALE Psen Pcon Power Control Register Smod IDLLocal Serial Channel Local Serial Port Mode ControllerSerial Port Mode Mode Load Sbuf Baud Rates Smod Timer 1 generated commonly used Baud ratesMHZ JNB SINGLE-STEP OperationReti 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 Frame Format CSMA/CD OverviewPreamble 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 ToleranceMissing 0-to-1 Transition Narrow PulsesUnexpected 1-to-0 Transition Response to a Detected Collision What the GSC was doing Resolution of CollisionsGSC Inactive TfifoDCR BackoffAlgorithm Prbs Tcdcnt Load Bkoff Slot Clock Myslot Random BackoffBKOFF= 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 Nrzi BIT Time Data EncodingBIT STUFFING/STRIPPING Line Idle Sending Abort CharacterAcknowledgement 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 MemoryDMA 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 Using the HOLD/HLDA Acknowledge ARB REQInternal 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 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
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