Back to Alpha Micro Pageant of Models | Alpha Micro Phun Machine @ Floodgap Retrobits

AMPM: Alpha Micro AM-1000 Series

As mentioned on the front page, the AM-1000 and its derivative models (AM-1000A, AM-1000E and AM-1000XP) are probably the most common Alpha Micro found in the wild, as much as any Alpha Micro can be considered common, of course. Many of these long-lived systems sat in corners doing their work for decades until they were eventually retired for more conventional Windows-based business computers; their form factor, while guaranteed to eat up most of a desk, did imply that they also found a niche as workstations in some environments. (However, they hardly replaced their elder S-100 server siblings; those continued to be a source of revenue for Alpha Micro and remained in production for several years after.)

The AM-1000 was succeeded by the AM-1200, which was in just about every respect a superior design.

Pictures

This is the original model Alpha Micro 1000 main unit and housing, with the optional 5.25" floppy, and standard 10MB internal hard disk. Although Alpha Micro refers to it as "lightweight" this should only be interpreted in comparison with Alpha Micro's other boxes; this case is fairly thick steel and kicking it is likely to damage your foot. No crapola mini-tower construction, this.

Rear ports. Three DB-25 serial ports are at the top left, with the five video control and data lines above the cooling fan, and four additional serial ports provided by an AM-336 on the right with an external SASI interface (more on that in a bit) below them. No AM-1000 series unit I have encountered has a serial number on its backplate (compare with the AM-1200 and the AM-1001 below), and the back is a black enamel colour instead of the typical brushed metal.

Unscrewing the side screws, removing the top and removing the top row of screws on the rear enables the motherboard to lift up like this. The 68000 CPU is the very large chip left of centre. A daughterboard connects to the top right.

Internal view. The AM-336 serial card and ports are at lower right with a ribbon cable connecting them to the mainboard. From left to right, the other boards are the AM-213 floppy drive controller (sitting on the power supply), the 800K 5.25" mech itself, and the SASI hard disk.

And, finally, the front panel. When started up, POST codes flash on the LED (more about that in the Potpourri section), culminating in 'b' which indicates the system has passed POST and is looking for a bootable system on the floppy or HD. The 'b' disappears when booting is in progress: see Potpourri below for important notes on testing these units out!

This unit appears to be in mostly working order, but I haven't finished fully restoring and testing it. It seems to fail a few things on the built-in self test but does find and load a system image on the main disk with no obvious errors. More on that when I get it cleaned fully and hooked up to its own terminal.

This AM-1000 came to me paired with an AM-1001, which is essentially a SASI drive in a AM-1000 case. The front panel only has a single power light, and no reset button or other status indicators.

Similarly, on the rear are no other ports save the SASI ports (and on this one the top one was in fact covered and disconnected; I removed the cover plate for comparison purposes). In its original environment, it connected to the host AM-1000 with the lower SASI port.

This later-manufactured system does have a serial number on its backplate, and is identified as an AM-1001 explicitly.

This AM-1001 had a grotesquely dirty interior and a drive that was literally in pieces; it made a horrible banging noise when I got everything reassembled and tried to power it up. I'm planning to rehabilitate it by cleaning it out and then installing a SCSI-1 drive to use it as a backup disk, but that will have to wait until I finish restoring the AM-1000 itself.

For interest, let's compare it with the first Alpha Micro I ever owned, the AM-1000E pictured here, identical to the base model except for a 30MB disk (removed here for photography). Alas, I discovered said disk was thoroughly recalcitrant despite much desperate coaxing and at the time I hadn't the space to keep in my apartment what was essentially a large, well made boat anchor. Fortunately, however, I was able to find the unit a good home with a very appreciative collector who used to use them in a repair shop many moons ago, so this unit lives on today.

Rear ports. Essentially this is the same as the AM-1000, and also includes an AM-336 for four extra ports. I left the coverplate over the external interface, which was not connected in this particular unit anyway. Notice that the back is now plain metal, but there is still no backplate serial number.

Inside the unit with the hard drive removed. The AM-336 can be seen here in the back, on the left; the mainboard and port headers is bolted to the top; and the power supply is to the right. The dud port connector for the disconnected interface can be partially seen under the AM-336.

"'b'ooting" -- after initial checks, a 'b' is displayed on the front LEDs and it starts looking for its operating system on the installed floppy or hard disk (which never extinguished in this unit). Notice this unit has a much nicer painted metal badge instead of the silkscreened badge of the original 1000.

Performance

Coming soon!

Potpourri

Look on the bottom for a list of installed hardware. This is usually accurate, at least with regard to what it left the factory with. (Even the AM-1001 has such a list, despite not being actually a computer.)
The earliest Revision A logic boards are much more difficult to upgrade. In fact, the hard disk and memory/port extender kits Alpha Micro sold required a Revision B board (the board revision should be listed on the bottom panel as well). All of the units I have encountered so far are Revision B or later.
Testing one of these guys out in the field is very important as quite a few have really taken a thrashing, but unfortunately Alpha Micro's Self Test Guide doesn't cover these models. Like other units, hold down the RESET button as you turn the device on for a full system check. The boot PROM will then start displaying codes on the LED for the current test; if there is an error condition, the code in question will start flashing. If you have a terminal connected at 300 baud (8N1) to port#1, a small amount of diagnostic output will also appear on the screen (useful for testing that the serial port works). Note that these oldest PROMs do not autosense baud rate.
- 88 - memory test (01 through 16 - memory failed)
- 81 - low memory test
- 9f - serial port test (90 - serial port 0 failed, 91 - serial port 1 failed, 92 - serial port 2 failed)
- af - timer test
- bf - Winchester (hard drive) test (b1 - controller self test, b2 - seek to diagnostic cylinder, b3 - write/read test)
- cf - VCR test (c1 - buffer RAM test)
- df - floppy drive test (d1 - RAM test, d3 - seek/read test, d4 - seek/read failed)
- ef - tape streamer test (not original AM-1000)
It is normal for bf, df and ef to blink if they are not installed options (but if they blink and the device is installed, then the device is either disconnected or the electronics are unresponsive). Thanks to Erik Petrich for this information.
NOTA BENE: Displaying 'b' on the LED does not mean that the drive is bootable, it just means that the system is trying to boot! A common mistake is assuming the drive is intact when 'b' appears -- don't make this error yourself! Hook up a terminal and make sure you see the operating system coming up before you assume the disk is operating!
Speaking of serial ports, for most installations you will connect your terminal at 9600bps (8N1), assuming a default system.
The fuse is 3A 250V (for 110 volt mains) or 1.5A 250V (for 240 volt mains).
Some notes on drive usage:
- The AM-1000 series' boot PROM is very small and matched to the Xebec HDC it comes with, which is only ST-506 or only SASI/"SCSI-1" (more about this in a second) in a given unit. That means if you want to put a SCSI drive into your ST-506 AM-1000, you'll have to find new boot PROMs, and Alpha Micro doesn't sell them any more. (Early AM-1000 motherboards didn't even get that right and had a design flaw where the ATN line on the SASI bus signaled incorrectly. The fix is reportedly not complex but I don't have it in my notes; if someone does, please send it in.)
  Original Alpha Micro drives have their controllers right on the hard disk (Xebec 1410 or 1410A controllers). This is quite vexing if the electronics fail, because these chips were only ever made for Alpha Micro as a special item.
- Even on those units where a SCSI drive is bootable, it's not really "SCSI": it just happens to act like it with certain SCSI-1 drives, but won't talk to SCSI-2 at all. An adaptor board is required to get "true SCSI" but it doesn't appear that this board was ever sold as an item (only in drive kits). Many old 68K Macintosh SCSI drives should work in this capacity, but their compatibility is often hit-or-miss.

Back to: Alpha Micro Pageant of Machines | Phun Machine Main Page