Ideal peripheral cards to integrate into a soft Apple design
The Apple Language Card designed by Wendell Sander was one of the first Apple cards available for the Apple II, released in 1979 with the Apple Pascal Language system. The Language card served two purposes; to provide an Autostart ROM F8 to earlier Apple systems that did not have the F8 boot ROM installed, allowing an Apple II to boot from a Disk Drive, and to provide an extra 16K of RAM to a fully expanded 48K Apple to bring the total memory available to 64k. As the Apple II evolved, the F8 ROM was eventually shipped as standard with the computer, and so the Language Card was soon no longer required. In 1980 Microsoft released their Microsoft 16K RAM card that provided the extra memory, but did not include the defunct F8 Autostart ROM.
Some of the more popular peripheral cards for the Apple II's
Apple Disk ][ Interface Card
Apple Model Number: A2S2128x
Apple 16K Language Card
Apple Model Number: A2S2128x
With the Apple II gaining popularity during 1978, Apple released several new peripheral boards to back up the Apple II computer system concept. Not only did this give the Apple II more capability, it demonstrated the power of the Apple peripheral board. It soon became apparent that with seven expansion slots, there wasn't much the little Apple II couldn't do. Woz's comprehensive, efficient design was highly expandable, and talented engineers right through the Valley started surrounding themselves with the right people to set up companies that would design and offer peripheral boards to the Apple II community. With an increasing number of boards on the market Apple's computing power was bolstered, and it became easier to sell the right configuration of an Apple II to the most demanding customers. The II's capabilities became seemingly unlimited. And on the dark side? Well, the marketers of the cloning companies could see how effective these peripherals boards were, and geared up to clone their own. All they needed were the designs. Most peripheral boards had few to no ASICs, were designed around only two sided PCBs, and as a result were highly susceptible to being copied. The boards were purchased, usually shipped to another country, photographed, then all the components removed and documented. The board was then ground down lightly using a type of glass paper to remove the solder mask and expose the copper traces. It was then photographed, and the image transferred to a new PCB raster scan exposure process where they would begin making their own copy boards.
In the FPGA world, we don't have to go to these lengths. All we need is either a register level understanding of the board's functionality, the schematics and any ROM code the card requires to operate. There are many Apple II boards that can add greater functionality and novel capability to the soft Apple. I have listed a few that I feel would certainly make a comprehensive setup as well as others that we have already included to provide an understanding of why they are required. Over time I hope to add the full suite of required information to allow these boards to be brought into the soft Apple FPGA domain, including ROM images, schematics, and software drivers.
The Disk II Interface Card was, and still is, one of Steve Wozniac's greatest designs. Released in 1979, the Controller with its Disk ][ Drive quickly demonstrated the new powerful capabilities of the Apple II when coupled with a floppy disk and an operating system (OS). The card's initial release was configured for a 13 sector based floppy format, but was soon upgraded to a 16 sector configuration. The 16 sector configuration and the card remained almost unchanged for the remainder of the Apple II series era, and the entire controller was eventually integrated into a single ASIC in 1982, called the IWM, or Integrated Woz Machine, and later in 1984 in the SWIM, or Super Integrated Woz Machine. These new ASICs were used in new systems released by Apple, including the Macintosh, UniDisk drives, disk controller peripheral cards as well as the Apple IIgs.
Several of the following peripheral cards are already included in some of the soft Apple designs. Those that are have the "Included" logo next to them. The cards are detailed here to show what they previously consisted of during the Apple II era, before being converted into a few lines of code by the modern FPGA engineer. There are also photographs of "Clone" cards to illustrate the bold identical copy approach the clone companies had towards designers of Apple cards.
Microsoft Z80 Co-Processor Card (Production)
Microsoft SoftCard - 1981
The Microsoft Z80 Card designed by Don Burtis was also known as the Softcard, and was the first Co-processor peripheral board available for the Apple II. The card was based on Zilog's popular Z80 microprocessor, and offered execution speeds of up to 4MHz. The card had a quick market uptake, and it was not long before the Apple II user community were taking advantage of the large business CP/M software library available to the Z80 processor. Many advanced applications were available in the C/PM domain that did not exist at the time in the Apple software libraries. Titles such as MicroPro's WordStar wordprocessor, as well as Spell Star, Zardax and dBase were all able to be used on the Apple II. As the demand grew for Z80 Co-processors, other vendors came onto the market; most copied Microsoft's Softcard design. Clone companies were quick to start selling identical copies of the Microsoft softcard, as well as integrating the popular Z80 softcard direct onto the main board. Unitron's 2200 Apple clone shipped with both the Z80 and 6502 as a standard "Dual processor" machine.
The Apple II Memory Expansion Card was a comprehensive large memory expansion card for the Apple II, IIe and IIgs. It expanded the II's memory to 1MB, which was significant in comparison to the 48K or 64K the machine was shipped with. The memory was arranged and managed in many banks of 16K, requiring special software to address and access it. ProDOS recognised this card and allowed memory use in applications such as RAM Disks, and additional memory for business programs such as AppleWorks.
The Apple II Video Overlay card was one of the more high tech designs released by Apple in 1986, towards the later part of the Apple II era. The card leveraged the majority of its capability from technology developed for the IIgs and shared the same project name, 'Gumby'. It was also the first time Apple used dynamic logic in the form of an early Xilinx FPGA known as an LCA, or Logic Cell Array. These static devices constructed logic processors and state machines at boot time on the card via a serial download, similar to how FPGAs today are configured. Maybe one of the more prominent features of the Video Overlay card is the fact that it contains a complete Apple IIe and the IIgs VGC, or Video Graphics Processor ASIC, all on a single board. This particular card not only gave the Apple II much higher resolution graphics, but also provided comprehensive video overlay and superimposing/summing features complete with GenLock to Apple IIs of all types. The Overlay card had the ability to accept video signals from cameras, VCRs and other broadcasting quality equipment. The bundled package included Apple's 'VideoMix' software that enabled graphics to be overlayed on PAL or NTSC Video images with broadcast quality from standard Apple II or IIgs graphics programs. The card was quite an expensive item, and is considered to be one of the rarer Apple cards around today.
The Saturn RAM card was one of the first large RAM cards to be made available for the Apple II. As a result, Saturn were in a good position to define addressing schemes for memory bank switching (paging) on RAM cards for the AII. During this time it was common to implement memory cards based on switching the 16k address space of the typical Apple Language Card. The method of instructing and indexing these changes had yet to be fully defined, and Saturn being the first to market adopted the de facto. The card was designed around the Motorola MC3242A bank switched memory controller, and consisted entirely of standard off the shelf semiconductor parts. With no ASICs or PROMS, the card became a highly attractive board to copy, and is one of the most common concisely copied cards from the Apple II era.
The Apple Mouse Card debut came in 1982, and was bundled with a version of MacPaint for the Apple II called 'Mouse Paint'. Designed out-of-hours by Apple's highly talented "usual suspects", the Mouse Card brought to the Apple II a new way of interacting with the machine, using the Macintosh style Mouse. After some time on the market, other Apple II applications began to appear with support for the Apple Mouse, including the popular AppleWorks business package. The Mouse soon became a popular approach to working with the Apple II. Unfortunately due to the Command Line Nature (CLI) and restricted graphics capability of the II, the Mouse was not as popular as it was with Apple's IIe or IIc, where programs such as Broderbunds Dazzel Draw with its double HiRES graphics made more effective use of the interface. When the IIgs was released in 1985 the Mouse Card, which had evolved into an ADB style interface, was integrated onto the main motherboard and the mouse was supplied with the IIgs as standard.
Development Platforms for reverse engineering popular Apple II cards
One of the many good reasons that made the Apple II one of the first truly popular systems was its ability to accept plug-in peripheral cards. Not only did this provide an incredibly versatile method of configuring and empowering the system, it also provided a road map that gave the machine a strong future through plug in technology upgrades. From generic RS232 to SCSI, the Apple II had a plug in card to enable it all. As part of the soft Apple concept, we wanted to create a platform allowing the plug in of any of the comprehensive array of existing peripheral cards, and the development of new cards, such as Ethernet adaptors, video, wireless and storage cards.
Enter Carte Blanche. The Carte Blanche peripheral board allows Nanoboard-style peripheral cards to be developed for use in the AII or AIII, using the Nanoboard or a real Apple as a development platform to design a card's functionality. Using Nanoboard-style plug on cards means development can be done either direct from the Nanoboard's peripheral slot, or via the Slots Board, where on completion the peripheral card can then be deployed in a real Apple II system. Carte Blanche came in two models - a Xilinx XC3S250E FPGA based version, and a comprehensive XC3S500E version. Both cards were designed around a low cost, easy to build, two layer standard Apple plug in peripheral card and came with several onboard standard peripherals of their own. The Carte Blanche II board (2015) continues on with this development.
For more information about the Carte Blanche II FPGA Peripheral Board, please click HERE.
PCPI's Applicard Z80 Co-processor
PCPI Model Number: 001-001-03
The Personal Computer Peripheral Inc's (PCPI) Z80 Appli-card co-processor board was released in 1982 to fast become one of the most popular Z80 cards available for the II series. The key reasons for success were primarily due to its rich features and low cost. This made the PCPI Appli-card not only a first choice amongst end users, but was also a popular item for other vendors who both licensed and cloned the board. Several versions of the card became available from other vendors, such as Franklin Computer, who released the board as the "ACE-80", mainly for sale with the Franklin 1x00 series. The board was also sold with the software word processor "Wordstar" by MicroPro as the Starcard, and sold as a complete bundle. Although 100% compatibility with the de facto Microsoft 'Softcard' was an ongoing issue, the Appli-cards onboard 64k or 128k memory, 6MHz Z80 processor, on card BIOS, and the optional feature connector, made the Appli-card one of the most powerful Z80 based peripheral boards available for the Apple II series.
The Microsoft Z80 SoftCard went through a minor PCB revision before the final production version of the card was completed. The following board is the initial release of the card (dated 1980) and has significantly different artwork to the final release. This version was used in the inital advertisements for the board.
During a correspondance with Don in late 2018, I took the opportunity to enquire why the Softcard had gone through a design/artwork update, and his response was:
"Sometime in 1980 or 1981 Apple changed the layout of their Apple II Motherboard. The new design used smaller width traces (with a small increase in inductance caused by the smaller traces). One of our customers had a problem with the Softcard reliably working in his computer. Microsoft had me buy (replace) that computer and the customer's Softcard so I could do extensive testing in my lab. Apple provided really good technical support as well. Once I realized the traces had been reduced, I tried compensating for the increased inductance on the clock line by adding a small capacitor. That cleaned up the clock signal and allowed the Softcard to work reliably on the new Apple motherboard layout (and the old Apple layout, too). I should mention we never received a complaint from any other user, so my determination was it resulted from a very unlikely marginal component tolerance condition - but the problem was real, so it needed to be fixed. That caused the new layout of the Softcard board."