Macintosh OS Ethernet Driver Design Specification Proposal Alan B. Oppenheimer May 18, 1987 The following is a proposal for a Macintosh Ethernet driver. It is envisioned to be useable for any Ethernet implementation (card, SCSI device, etc.). The interface is such that it should also be applicable to other networks (e.g. Token Ring) with little or no changes. This proposal is for a general-purpose Ethernet driver, and does not address the issue of Apple Talk protocols running on Ethernet hardware. It conforms to IEEE 802.2 Type 1 service. Macintosh network developers are familiar with the Apple Talk driver interface; this interface is patterned directly after that. See the Apple Talk Manager chapter in volume 2 of Inside Macintosh for data structure details. Opening the Ethernet ddyer: The Ethernet driver is opened through a device manager Open call, indicating the slot (for a Mac II) in which the Ethernet card is installed. The driver is initially opened in "Apple Talk" mode. In this mode, packets sent by the driver are restricted to a maximum of 768 bytes. This is big enough to encapsulate AppleTalk packets, and allows more of a shared buffer pool to be allocated for packet reception. The driver can be changed to "general" mode, where it will transmit any valid Ethernet packet, through a control call defined below. The name of the Ethernet driver is '.ENEr. Commands to the Ethernet driver: Commands to the Ethernet driver are specified by means of Device Manager Control calls, with arguments passed in the queue element starting at CSParam. The following is a list of commands: EAttachPH: attach a "protocol handler" to the driver. Arguments are a two-byte protocol type and a handler address. The handler will be called (see "protocol handlers" below) when a packet of its type is received. If the protocol handler address is zero, a "default" protocol handler will be supplied by the driver which will enable the caller to issue standard read calls for that protocol type (see the ERead call). Note: to attach (or detach) a handler for 802.3 (which use protocol types O through $5DC), specify protocol type zero. EDetachPH: detach (remove) the protocol handler for the given protocol type. All pending reads are aborted with an error. EWrite: write out a packet on the Ethernet. The only argument is a WDS (write data structure) pointer. The WDS is a series of length/pointer pairs, terminated by a zero length. The data is "gathered" from each of the WDS entries, in the order provided. The first entry must start with the destination address (6 bytes for Ethernet), and then contain 6 unused bytes (in the Ethernet case) followed by the two-byte protocol type field. Data may then follow if desired. Ethernet Driver - DRAFT Apple Confidential Page 1 If the total length of the packet is too big (greater than 1514 bytes if "general", or 768 bytes if "AppleTalk" mode) an error is returned. If the total length of the packet is too small (less than 60 bytes for Ethe…

EtherTalk Packet Formats - Draft Proposal May 18, 1987 Apple Network Systems Development Scope: this document specifies details of AppleTalk packets sent on Ethernet. Details: AppleTalk packets on Ethernet are sent using Ethernet protocol type $8098. They contain the standard 1~-byte Ethernet header (destination, source, type) followed by the full AppleTalk packet as defined in Inside AppleTalk. Specifically, an AppleTalk packet consists of the three-byte ALAP header (ALAP destination, source, type), followed by the ALAP data field, the first two bytes of which must be the ALAP data field length (the high six bits of the length field are ALAP protocol-dependent). If the packet is being broadcast, the ALAP destination must be $FF. Ethernet packets have a minimum size of 60 bytes. Including the Ethernet header, an EtherTalk packet could be as small as 19 bytes. Thus small EtherTalk packets must be padded to 60 bytes in length. The pad bytes should all be zeroes. Note that the receiving node can determine the actual packet length from the ALAP data field length bytes. The maximum size of an EtherTalk packet is 603 + 14, or 617 bytes. Ethernet Oestinatio '' Ethernet Source Ethernet rotocol T e $8098 ALAP dest ALAP source ALAP type LAP data length ALAP data Pad flf needed) May 18, 1987 EtherTalk Draft -- Apple CONFIDENTIAL 1

Apple Confidential TFB Specification UPDATES TO THE SPECIFICATION The following is a list of changes made to the frame buffer specification for the 28 June 1985 version of the document. 123456789- Support for the planar color model has been dropped from section 1.3. The frame buffer memory map has been updated in section 2.0. Many of the control register definitions have changed in section 3.0. Several pin definitions have changed in section 4.0. Test mode operation has changed, and is explained in section 4.3. Planar mode accesses have been eliminated. Data transfer cycles are changed in section 5.2. Appendix A has been added to suggest possible configurations using the TFB. Timing information has been added in Appendix B. The following is a list of changes made to the frame buffer specification for the 1 February 1986 version of the document. These changes apply only to the 1.1 version of the TFB. 12345678911 10 - Support for variable depth color has been added to the chip. Support for multiplexed address and data buses has been added to the chip. The speed of the chip has been increased substantially. The bus interlace has been simplified. The chip parameter descriptions have been rewritten and elaborated on. The SCl-pin has been eliminated in favor of a pixel clock output pin. The DS- pin has been eliminated in favor of a dedicated test mode pin. The definitions and timing of the WEN and CMA buses have been changed. All of the figures and diagrams have been updated. Several configuration paramenter have been added. The appendicies have been updated. The following is a list of changes made to the frame buffer specification for the 24 October 1986 version of the document. These changes apply only to the 1.2 version of the TFB. 12- Only rowbytes which are powers of two are supported. The CMA bus definition has changed. 7 November 1986 1 Toby Farrand Apple Confidential TFB Specification TABLE OF CONTENTS 1.0 INTRODUCTION 3 1.1 1.2 1.3 3 4 How to Read this Document System Configuration Features 2.0 DATA ORGANIZATION 5 3.0 CONTROL REGISTER DESCRIPTION 5 3.1 3.2 3.3 3.4 4.0 5.0 System Configuration Parameters Horizontal Timing Parameters Vertical Timing Parameters Initialization Procedure 6 9 11 12 SIGNAL DESCRIPTION 12 4.1 4.2 Inputs Outputs 13 15 Bus Operation 17 5.1 5.2 5.3 17 17 18 RAM Cycle Data Transfer Cycle Refresh Cycle 6.0 Future Directions 18 6.0 Conclusion 19 Appendix A - Application Note. 20 Appendix B - Electrical Specifications. 24 Appendix C - Pinout and Mechanical Data. 31 7 November 1986 2 Toby Farrand Apple Confidential TFB Specification 1.0 INTRODUCTION One distinguishing characteristic of Apple's computer products is the tight coupling our machines have between their memory and video systems. This tight coupling results in products which have superior graphics in terms of resolution, speed and cost. This architecture's costs are significant,however, as the video refresh…