MacPlinth 7323

Albis, Albiswerke AG (Siemens Switzerland AG / Telefunken Zürich AG / Siemens-Albis); Albisrieden

Données
Forum
Images
Collections

  • Année
  • 1984
  • Catégorie
  • Processeur de signal et informatique
  • Radiomuseum.org ID
  • 358258

Cliquez sur la vignette du schéma pour le demander en tant que document gratuit.

 Spécifications techniques

  • Gammes d'ondes
  • - sans
  • Tension / type courant
  • Alimentation externe ou alimentation principale / DC 5 Volt
  • Haut-parleur
  • - - Pas de sortie basse fréquence
  • Matière
  • Circuits imprimés
  • De Radiomuseum.org
  • Modèle: MacPlinth 7323 - Albis, Albiswerke AG Siemens
  • Forme
  • Chassis (pour intégration dans meuble)
  • Dimensions (LHP)
  • 225 x 25 x 240 mm / 8.9 x 1 x 9.4 inch
  • Remarques

  • Steve Job's conception of the original 'compact' 1984 Macintosh computer was that of a closed box that would never be opened or upgraded by the user. Even the RAM chips were soldered directly to the motherboard, making it difficult to change them when higher density components became available. This view wasn't shared by the Macintosh design team, who argued that the computer should have at least one slot for cards that could add functionality and connect it to the external world. They attempted to provide this connectivity by including a 'diagnostic port' that provided access to the 68000 microprocessor bus, but this was vetoed by Jobs when he realised its real purpose.

    This lack of connectivity was a challenge to users who wanted to apply the Mac in industrial and research work that required the computer to control and monitor external systems, such as CAMAC and VMEbus. One solution that was designed by Bruce Taylor and manufactured by Siemens Albis SA was a pcb called MacPlinth that mounts under the Mac cabinet and becomes an integral part of the computer. MacPlinth was supplied in the form of a kit including detailed instructions and all the parts, and it could be installed by an electronics technician in less than an hour. It can access a total of over 100 Mbytes of external address space, in up to 8 VME crates containing V370 VMEbus controllers, or up to 7 VME crates and up to 8 CAMAC crates containing 392 Mac-CC crate controllers. MacPlinth also provides a composite video signal for additional remote monitors, and can accommodate 128 Kbytes of local EPROM for permanent library enhancements.

    The VME or CAMAC crates simply appear within the address space of the microprocessor, so that no special software drivers are required to access them. A Schottky 'Emmental' PROM on MacPlinth maps each 64 Kbyte segment in the 68000 address space to internal Mac space, MacPlinth EPROM, external system space or external common space. A second level of mapping allows the external space to be allocated dynamically to any of up to 8 VMEbus crates. The Mac can execute code in VME RAM or EPROM, and programs resident in one crate can access facilities in any of the others.

    Mac internal interrupt codes are decoded on MacPlinth, merged with external interrupt sources, and re-encoded before application to the 68000. During a Mac IACK bus cycle, MacPlinth decodes the interrupt level being acknowledged from the LS bits of the address bus. If the level is one that has been assigned to external system interrupts, the assertion of VPA* by the Mac interrupt circuitry is inhibited, and a vector number is fetched from the VME interrupter via the V370 master module. In a multi-crate VME system, MacPlinth automatically accesses only the crate containing the source of the interrupt, independent of the map No. currently in its control register.

    MacPlinths were fitted to many Macintosh, Macintosh Plus and Macintosh SE computers. Following the introduction of the modular Macintosh II family having a NuBus card cage, it was superseded by A410 MICRON, which can drive the same CAMAC and VMEbus controllers.

     

  • Poids net
  • 0.5 kg / 1 lb 1.6 oz (1.101 lb)
  • Littérature
  • -- Original-techn. papers. (MacVEE User Manual)
  • Auteur
  • Modèle crée par Bruce Taylor. Voir les propositions de modification pour les contributeurs supplémentaires.

 Collections | Musées | Littérature

Collections

Le modèle MacPlinth fait partie des collections des membres suivants.

 Forum