Big Book of Amiga Hardware

Standard Specifications

NOTE: These specifcations apply to the A4000T made by Amiga Technologies, and do not necessarily apply to the A4000T made by Commodore.

When Escom bought the Amiga operation after the liquidation of Commodore, they established an Amiga subsiduary called Amiga Technologies and began the reproduction of A4000Ts (Commodore made approximately 200 units). The A4000T is arguably the best official Amiga ever made. It is easy to assume that the A4000T is simply the same motherboard as the desktop A4000, but this is not the case. The A4000T uses a totally separate motherboard. The A4000T is intended to be a large AT form factor motherboard and infact appears to use a standard PC AT power supply. Unlike the desktop version, the A4000T also includes an NCR 53C710-based Fast SCSI-II controller on the motherboard in addition to a 3.5" IDE controller. This is why the A4000T uses a slightly different version of Kickstart 3.1 compared to other Amigas (including the A4000). It contains the drivers for the SCSI-II controller in ROM and in order to allow it to fit, workbench.library was moved from ROM, supplied on the Workbench disks and is loaded from LIBS: like any other disk based library. The A4000T also contains an internal speaker for native sound output, however external speakers and headphones can also be used. The speaker can be disabled or enabled by pressing the button labelled "Turbo". The case also contains a reset button as well as a key lock. The A4000T also uses coin shaped lithium batteries unlike most Amiga models which use the barrel shaped batteries. The A4000T contains 4 x 72pin SIMM slots for adding up to 16MB of RAM in addition to the 2MB of Chip RAM surface mounted on the motherboard. SIMM sizes of 1MB, 2MB, 4MB and 8MB can be used. Please note, than even though it is possible to use 8MB SIMMs, you are still limited to 16MB on the motherboard. If 8MB SIMMs are used, only 2 SIMMs can be used and they must be inserted in alternate slots (they are treated as 2x 4MB and wired to a pair of sockets). All of the external connectors in the A4000T reside on little cards which in turn connect to the motherboard. This means they could easily be replaced or upgraded and infact some companies did release alternate cards for the small PCB containing the video related ports. The A4000T uses the 5pin DIN keyboard connector, unlike the PS/2 style connector which the A4000 uses. Unusual for Amigas, the A4000T does NOT have an external floppy drive connector, however two internal drives can be used.

QuikPak 68060 Accelerator

The QuikPak 68060 is a direct decendant of the GVP/TekMagic T-Rex II 68060 accelerator.  The card is very similar to them, but it does not have any SCSI controller components on it.  QuickPak, then-based in the surrounding-county suburbs of Philadelphia, and around the time of the Amiga Technologies production restart, was headed by Dave Zimbecki.  He was the former VP of Operations at Great Valley Products (1988-1994, and previosly he was at C= in the early C64-era).   His long term relationship with Jeff Boyer, VP of Enginering at GVP (owner of the later TekMagic brand, and also a former C= HW engineer), resulted in this high-end 68060 card being made for many of the top-spec A4000T 68060 units.  These cards tend to benchmark slightly higher on memory performance tests than other very good 68060 accelerators of the time (including the GVP/TekMagic T-Rex II 68060) as they were some of the earliest designs to optimally support both EDO memory and the 68060's burst mode.  Although the board never shipped with the Ralph Babel 68060.library (licensed to the earlier GVP/TekMagic 68060 products), they are fully compatible with both Ralph's 68060.library, and the MuLibs CPU library package.

IDE Interface Notes:

The Amiga 4000T (and D) 40-pin IDE, and it's A1200 44-pin relative, require the older Master/Slave form of IDE devices in order to use two devcies on that interface.  Many modern (i.e. - cheap) IDE CF/SDflash-adapters and industrial Flash-DOM modules only support a CableSelect (CS)-type connectivity.  Many have no jumper to choose a fall-back to a legacy IDE device behavior as many spinning-media IDE hard disks have.  When a CS device is on the interface, a second (slave) devcie will not be recognized.

Ultrasound Medical Imaging System

A series of post-Commodore era units based loosely on the Amiga Technolgies A4000T configuration were assembled for a special ultrasound medical diagnostic appliance in the mid-late 1990's.  These units contained a custom 60MHz version of the GVP/TekMagic accelerator board with 64MB RAM (4x 16MB 72-pin SIMMs).  This board is a cousin of the GVP/TekMagic A4000 T-Rex II 68060-series accelerators without the 53C710 SCSI components, but has 2x custom ribbon-cable interfaces to support the specialized medical hardware (DSPs and other processors) which was designed for the medical imaging process.  Most of these appliances were eventually recalled by the maker (medical gear is commonly leased) after their medical service/support life ended, to be replaced by the next generation of medical ultrasound hardware.  A few of these units, sans the ultrasound-specific medical imaging hardware, survied e-waste disposal, and are extremely rare.  The system booted from the native SCSI interface and HD via Kickstart 3.1, but jumped directly into the custom medical software.  Performance of the accelerator card is on par/slightly less than the T-Rex II 68060 due to the slightly lower clockspeed.  All CPU-support software compatible with the GVP/TekMagic 68060 products will work with the 68060 accelerator.

Jumpers

Disk Module Jumpers

Note: The small PCB where the serial port, parallel and video port are connected also contains a 50pin connector. This is actually a terminator for plugging the end of the SCSI cable into