Texas Instruments TMS380C26 specifications 80x8x mode bus release timing, Sbrls Sown, TW or, 208c

Page 74

TMS380C26

NETWORK COMMPROCESSOR

SPWS010A±APRIL 1992±REVISED MARCH 1993

PARAMETER MEASUREMENT INFORMATION

80x8x mode bus release timing

NO.

PARAMETER

MIN MAX

UNIT

208a

Setup of asynchronous input

low before SBCLK no longer high to guarantee recognition

15

ns

SBRLS

208b

Hold of asynchronous input

low after SBCLK low to guarantee recognition

15

ns

SBRLS

208c

Hold of

low after

high

0

ns

SBRLS

SOWN

T(W or 2)

T3

T4

T1

T2

SBCLK

208a

SBRLS (see Note A)

208b

SOWN

208c

NOTES: A. The System Interface ignores the assertion of SBRLS if it does not own the system bus. If it does own the bus, then when it detects the assertion of SBRLS, it will complete any internally started DMA cycle and relinquish control of the bus. If no DMA transfer has internally started, then the System Interface will release the bus before starting another.

B.If SBERR is asserted when the System Interface controls the system bus, then the current bus transfer is completed, regardless of the value of SRDY. If the BERETRY register is non-zero, the cycle will be retried. If the BERETRY register is zero, the System Interface will then release control of the system bus. The System Interface ignores the assertion of SBERR if it is not performing a DMA bus cycle on the system bus. When SBERR is properly asserted and BERETRY is zero, however, the System Interface releases the bus upon completion of the current bus transfer and halts all further DMA on the system side. The error is synchronized to the local bus and DMA stops on the local sides. The value of the SDMAADR, SDMADDRX, and SDMALEN registers in the System Interface are not defined after a system bus error.

C.In cycle-steal mode, state TX is present on every system bus transfer. In burst mode, state TX is present on the first bus transfer and whenever the increment of the DMA Address Register carries beyond the least significant 16 bits.

D.SDTACK is not sampled to verify that it is deasserted.

E.Unless otherwise specified, for all signals specified as a maximum delay from the end of an SBCLK transition to the signal valid, the signal is also specified to hold its previous value (including high-impedance) until the start of that SBCLK transition.

Figure 36. 80x8x Mode Bus Release Timing

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Image 74

Contents Network Commprocessor Attached System Bus LAN SubsystemPinout PIN Quad Flat Pack TOP ViewDescription Block diagram and signal descriptions PIN Name Description TMS380C26Terminal Functions Maxpl MaxphAX1 AX0 AX3 AX2MOE SresetMreset OUT MrasPrtyen NSELOUT0 NSELOUT1= H SbheSintr Sddir Direction DIO DMAShrq SRD SWR= Selects 16-bit mode 108 Reserved. This signal must be left unconnected see Note= Selects 8-bit mode see Note SyncinSBHE/ Srnw System Interface ± Motorola Mode SI/M= L Sbrq Terminal Functions = LSbgr SirqSlds SudsSdtack Pxtalin FRAQ/TXDNsrt RCVR/RXDColl LpbkTXC Terminal Functions VSS3 VsslVSS1 VSS2 VSS4 VSS5 VSS6System interface SIF ArchitectureCommunications processor CP Memory interface MIF Protocol handler PHAdapter support function ASF Clock generator CGAdapter-Internal Pointers for Token-Ring² Address DescriptionAdapter-Internal Pointers for Ethernet ² Word Transfers User-Access Hardware Registers³ 68xxx Mode is always 16-bit Byte TransfersSIF Adapter Control Register Sifacl Bits 0-2 Test 0±2. Value on Test 0±2 pinsBit 5 Swddir Ð Current Sddir Signal Value Sifacl RegisterBit 8 Areset Ð Adapter Reset Bit 6 Swhrq Ð Current Shrq Signal ValueBit 7 Psdmaen Ð Pseudo-System-DMA Enable Bit 10 Boot Ð Bootstrap CP CodeBit 14 Ð 15 Nselout 0±1 Ð Network selection outputs Bit 12 Sinten Ð System-Interrupt EnableBit 13 PEN Ð Adapter Parity Enable System Psdmaen Swhrq Swhlda Sinten Interrupt ResultDMA SHRQ/SBRQ Sifacl Control for Pseudo-DMA OperationSysteminterrupt SINTR/SIRQ Dmadir Sddir Swhlda Swddir Swhrq Psdmaen SintenParameter Test Conditions MIN TYP MAX Unit Recommended operating conditionsMIN NOM MAX Unit See NoteVload IOL Test measurementHigh Low Output Under TestClkdiv = Oscout MBCLK1² MBCLK2² Reference PeriodsWhen Signal Function Static signalsTiming parameter symbology Timing parametersReaches minimum high level 289² ThRST Hold time of DMA size from High Intel mode onlyParameter MIN MAX Unit HVDDH-RSL 118² Pulse duration High103 VDD Sbclk Oscin MBCLK1 MBCLK2 Sreset S8/SHALTMinimun VDD High Level 101 106 104 105 102 107 110 108 109 111 117 118 119 288 289NMI 126 Delay time from MBCLK1 no longer low to ValidMreset 121 Hold time Valid after MBCLK1 lowMADH0±MADH7 MresetMBCLK1 MBCLK2 MAX0 MAX2 ADD/EN Mromen Maxph Maxpl Mromen MAL Memory bus timing clocks, MRAS, MCAS, and MAL to AddressMADL0±MADL7 Maxph Maxpl Address Status Column RowAddress Column StatusMaxph Maxpl MADH0±MADH7 Memory bus timing read cycleMcas MOE Maxph MaxplAddress Status Data/Parity MAX0 MAX2 MromenMras Mcas MbiaenMemory bus timing write cycle MAX2 Mromen Enable AddressMAX0, Address Mras Mcas MbenMemory bus timing TMS380C26 releases control of bus Parameter MINMddir MAL Mbiaen Mbrq Mbgr MBCLK1 MBCLK2 Mben75a 74a Hold time Valid after MBCLK1 low, bus resume Setup time High before MBCLK1 rising edge, bus resumeMemory bus timing TMS380C26 resumes control of bus Memory Bus Timing TMS380C26 Resumes Control of Bus Mben Mddir MAL Mbiaen Mbrq Mbgr Hold time Low after MBCLK2 low, external bus master read Memory bus timing external bus master read from TMS380C26Macs Mddir Macs MBCLK1 MBCLK2MAX0 MAX2 Maxph Maxpl MADH0±MADH7 Data/Pty Memory bus timing external bus master write to TMS380C26MAX0, MAX2 Maxph Maxpl 73a Memory bus timing Dram refresh timingMADL0±MADL7 Mras Mcas Mref127 128 Xmatch and Xfail timingBit Xmatch XfailRclk Token ring Ð ring interface timingParameter MIN TYP MAX Unit RcvrDrvr Token ring Ð transmitter timing see FigureRclk or Pxtalin 160 159TXD Ethernet timing of clock signalsEthernet timing of Xmit signals TxenRXC Ethernet timing of RCV signals Ð start of frameCRS RXD320 321 Ethernet timing of RCV signals Ð end of frameCrshld 322TXD Txen Ethernet timing of RCV signals Ð no RXCNorxc Data 350TXC TXD JAM80x8x DIO read timing Sras SCS, SrsxSRS0± SRS2 Sbhe Sdben80x8x DIO write timing 281a Valid 264 265 268 256267 272a 280 281 282W 283W 276 279 275 282bSRD, SWR SCS Siack 80x8x interrupt acknowledge timing ± first Siack pulse80x8x interrupt acknowledge timing ± second Siack pulse 287 First 286 SecondSdben SRDY²HI-Z SCS, Srsx SRS0±SRS2 Sbhe Siack SWR SRDSddir High SADH0±SADH7 SADL0±SADL7,HI-ZSPH, SPLSRD SWR 80x8x mode bus arbitration timing, SIF takes controlSown SWR SownSADL0±SADL7 SPH, SPL Sbbsy ShldaSRD, SWR This cycle 208b After Sbclk low to guarantee recognition on this cycle212 Delay from Sbclk low to address valid 214 ² High TwSCKL ±Sbclk Sras 80x8x mode DMA write timing SldsSADH0±SADL7 SPH, SPL SRD HighSADL0±SADH7 Sddir High80x8x mode bus arbitration timing, SIF returns control TW or 80x8x mode bus release timingSbrls Sown 208c68xxx DIO read timing Suds Slds SRS0, SRS1Siack Srnw SDTACK²HI-Z SADH0±SADH7 SADL0±SADL7,HI-Z SPH, SPL68xxx DIO write timing Suds Slds SdtackSDTACK² SCS SRSX, SRS0, SRS1 Siack SrnwSDBEN³ SADH0±SADH7 SADL0±SADL7,HI-Z SPH, SPLSCS Srnw Sdtack 68xxx interrupt acknowledge cycle timingSCS Siack Siack SdtackSADH0±SADH7 SADL0±SADL7, HI-ZSPH, SPL SCS, Srsx SRS0, SRS1 Sbhe Siack Srnw SldsSdben SDTACK² HI-Z 275 282a 255Sbgr 68xxx mode bus arbitration timing, SIF takes control241 Delay from Sbclk high in TX cycle to High SbrqSuds Srnw Sberr Sdtack SbbsySAS, Slds SADH0±SADH7 HI-Z SADL0±SADL7 SPH, SPLOn this cycle 208b 68xxx mode DMA read timing237R Delay from Sbclk high in the T2 cycle to Low Suds SASSale SADL0±SADH7 SADH0±SADL7 SPH, SPL 68xxx mode DMA write timing Sdben Suds SldsSAS SADL0±SADH7, SADH0±SADL7 SPL, SPH68xxx mode bus arbitration timing, SIF returns control 240 ² Setup SRNW,SIF HI-Z Sbclk Sbgr SdtackRead HI-Z Write Write ReadSbrls Sown 68xxx mode bus release and error timingSown Sberr Sberr SdtackSbclk Sdtack Sberr Shalt Rerun cycle with delayed start²Normal completion with delayed start² TH B TH E Sbclk Sdtack Sberr Shalt SownJedec NO. Outline Terminals MIN MAX Jedec plastic leaded quad flat package PQ suffix254 0.010 NOM 635 0.025 NOM 76 0.030 NOM MO±069±ADImportant Notice