DIRECTORY CoreCreate; SloIODevice: CEDAR DEFINITIONS = BEGIN EthernetController: PUBLIC PROC RETURNS [ct: CoreCreate.CellType]; --Intel82586 HardDiskController: PUBLIC PROC RETURNS [ct: CoreCreate.CellType]; --Am9580 SerialCommController: PUBLIC PROC RETURNS [ct: CoreCreate.CellType]; --Z8530 CounterIOUnit: PUBLIC PROC RETURNS [ct: CoreCreate.CellType]; --Z8036/8536 IOPMicroprocessor: PUBLIC PROC RETURNS [ct: CoreCreate.CellType]; --Intel80186 SloBusArbiter: PUBLIC PROC RETURNS [ct: CoreCreate.CellType]; --Intel8289 SongBoardInterface: PUBLIC PROC RETURNS [ct: CoreCreate.CellType]; --Intel8255A PIA IOPController: PUBLIC PROC RETURNS [ct: CoreCreate.CellType]; --Standard Cell part END. Behavioural Model of Intel 82586 Ethernet Chip Read: IOP asserts CA ENC finishes prior task; drops CA (and INT) ENC clears internal IIT status ENC aquires SloBus IOP asserts READY ENC performs Read transfer Check for frame arrival (IIT bit may get set) ENC releases SloBus If (internal IIT) then ENC asserts INT else idle Write: ENC asserts INT IOP asserts READY ENC clears internal IIT status ENC aquires SloBus ENC performs Write (byte; "octet") transfer Check for frame arrival (IIT bit may get set) ENC releases SloBus until Rx FIFO threshold If (internal IIT) then ENC asserts INT else idle SloBus Setup: Acquire: ENC asserts HOLD IOP asserts HLDA Frame Reception: Frame received from RU Post receive frame processing usurps at least 173 CLKs on the SloBus Release: ENC deasserts HOLD first IOP deasserts HLDA Relinquish: IOP asserts RESET for minimum of 4 CLKs ENC relinquishes SloBus within 10 CLKs If transaction still pending then ENC reasserts HOLD after 1 CLK Memory Transfers: Each DMA transfer consists of at least 4 CLKs (t1, t2, t3, t4) During t1: ENC generates address During (t2..t3): data transfer occurs Wait states: If ~READY then insert wait states øSloIODevice.mesa Copyright c 1986 by Xerox Corporation. All rights reserved. Created by Neil Gunther, August 14, 1986 2:05:36 pm PDT Last Edited by: Neil Gunther August 25, 1986 6:46:01 pm PDT The following procedures refer to IOPMSI.dale Êý˜šœ™Icodešœ Ïmœ1™K˜ K˜%Kšœ.˜.—K˜—…—‚ w