Last-modified: Mon Feb 7 14:17:40 EST 1994

Version: 3.01

TABLE OF CONTENTS:

  1. L1. What can be done about older 030 NeXT cubes that have a fan that turns in the "wrong" direction?
  2. L2. Can I connect SONY MPX-111N to my 68030 NeXT Computer?
  3. L3. Why does the OD continually spin up and spin down?
  4. L4. How many colors can NeXT machines display?
  5. L5. Why is my machine so slow when I run the monochrome and NeXTdimension displays?
  6. L6. Where to obtain replacement mouse parts?
  7. L7. Where to obtain extra batteries?
  8. L8. How to convert a Turbo system to use ADB?
  9. L9. How to put a 68030 board in the same NeXTcube as a 68040 board?
  10. L10. How to expand DSP memory?
  11. L11. How to boot a NeXT without a monitor?

Subject: L1. What can be done about older 030 NeXT cubes that have a fan that turns in the "wrong" direction?

The fan on older 030 NeXTs cubes sucks air out of the back of the cube which means that it draws unfiltered air in through the optical disk on the front of the cube. This causes optical disks to succumb to dust must sooner than cubes with the new-style fan which turns in the opposite direction.

NeXT has apparently reversed their decision regarding fan reversal in the case of machines that have been upgraded to 040 processor boards. It is now considered okay to reverse the direction of fans in these machines. If you have many third-party cards installed in your cube or an older processor board, you may wish to consider not reversing fan direction (overheating could become a problem). In any case, do not reverse the fan's polarity, only reverse the fan assembly itself. Perhaps the best solution is obtain the cleaning kit and OD filter from NeXT.

Subject: L2. Can I connect SONY MPX-111N to my 68030 NeXT Computer?

The SONY MPX-111N internal 2.88 MB floppy drive which was shipped with all the 68040 NeXT machines is *not* a SCSI device, therefore there is no way of connecting that particular drive internally on a 68030 system.

Subject: L3. Why does the OD continually spin up and spin down?

A big problem with the Canon optical drives is that air flows through the drive to cool it. Dust accumulates inside the drive causing it to fail with the continuous spin-up spin-down syndrome. NeXT as part of it's 040 upgrades provided a dust filter to prevent this. If your drive has this problem it usually can be fixed simply by cleaning out dust from the drive. NeXT sold a cleaning kit for both the drives and the optical disks.

Subject: L4. How many colors can NeXT machines display?

The monochrome machines can display 4 gray levels. You can use color apps on a monochrome machine, they will converted into monochrome images and dithered accordingly.

Color NeXTstations can combine 4 bits of red, green and blue primaries for a total of 4096 "pure" colors. The imaging functions dither the image to produce intermediate colors.

NeXTdimension can combine 8 bits of red, green and blue for 16,777,216. There are not 16 million points on the display so all can not be displayed at once. Further display technology limits the usable color space.

None of the NeXT products support color look up tables where the user can define their own color palette on a per window basis. This feature is useful for displaying images which have adaptive lookup tables, and display pure grayscale images on the color NeXTstation. On the NeXTdimension images can be converted to full 24 bit representation.

Subject: L5. Why is my machine so slow when I run the monochrome and NeXTdimension displays?

There is a bug with the window system in which if you select the monochrome display as your primary display the server will be much much slower. The solution for those wishing to use both displays is to select the color (NeXTdimension) display as the primary display. The most optimal configuration at present with the NeXTdimension is to run only the color display.

Subject: L6. Where to obtain replacement mouse parts?

[[email protected]]

For those who have need of a new button in their mouse, and don't want to pay for the whole mouse when it is only the button that has gone bad, we have recently discovered a satisfactory replacement for the Omron switch. It is in the Digikey catalog, # 931, Jan-Feb 1993, page 141, under Cherry switches D4, DG, and DH series. Digikey part # CH164-ND, Cherry part # DG1C-B1AA. We ordered one of these, and just received it today. Tried it out, and it sems to be working flawlessly so far.

Subject: L7. Where to obtain extra batteries?

Battery part number: BR 2/3A 3V Lithium Battery (Panasonic)

Source: Engineered Assemblies & Components Corporation

5204 Green's Dairy Road Raleigh, NC 27604 Phone: 919-790-9700 (ask for Debra) Price: $16.71 for 2 batteries incl. shipping & C.O.D.

Subject: L8. How to convert a Turbo system to use ADB?

[From: [email protected] (Brad Sime)]

If ADB equipment are used with older NeXT systems they won't work properly.

Here are the ADB requiments:

Subject: L9. How to put a 68030 board in the same NeXTcube as a 68040 board?

[[email protected]]

***************** DISCLAIMER DISCLAIMER ********************* The following procedure is not supported by NeXT, Inc. and will definitely void the warranty on your NeXT computer. Follow it at your own risk. I disclaim all responsibilities for damages caused by negligence in following the procedure. There is no guarantee that the procedure will work on all versions(?) of the NeXT cube hardware. All I know is that it worked on the NeXT cube I was working on!!!! SO BEWARE! ***************** DISCLAIMER DISCLAIMER ********************* Here we go! I'll first provide a description of the hardware I was using and comment on what I accomplished and how I got the information on how to do it!

The hardware included a NeXT cube with 660 MB drive, OD, etc., a 68040 upgrade board, and a 68030 motherboard. I successfully installed both the 68040 and 68030 boards on a SINGLE NeXT cube and linked them together through their ethernet ports. The 68040 was configured as a boot server and the 68030 was used as its client (booting off the network for lack of an additional hard drive).

The procedure reconfigures slot #2 on the cube's back-plane as slot #0. This provides two slots configured as #0, required for booting the two motherboards. Once I determined what the slot pin-outs were (thanks to my good friend John Chmielewski), it was a matter of time before the two boards happily co-existed.

The procedure:

  1. 1. First, follow the procedure on the NeXT User's Reference manual for removing the system board (Appendix C: Opening the Cube, page 291 of the 2.0 manual).
  2. 2. Using the NeXT supplied screwdriver, remove the two screws that attach the power-supply housing to the cube (the screws are located on the lower part of the housing) and gently pull the housing out. Set it aside in a safe place (away from kids and nosey friends!).
  3. 3. Remove the two plastic grooved plates (used to slide the system boards in) at each side of the inside bottom of the cube. (For each plate, lift the side closest to the rear opening and gently pull them out). Set them aside.
  4. 4. Using the NeXT tool, remove three screws holding the back-plane to the cube and then take the back-plane out of the cube. Let the cube rest for a while. Inspect the back-plane. You will see five bus slots (four vertical and one horizontal). The horizontal slot connects the back-plane to the power supply housing. We're only interested in the four vertical slots. From the factory these slots are configured as 6, 2, 0, and 4 (starting from the left and going right with the horizontal slot at the bottom). The system board connects to slot #0 (which you've probably noticed). Each slot contains three columns of 32 pins. Following is an ASCII representation of one of the slots:

    x y z C B A o-o o 32 . . . o-o o 31 . . . o-o o 30 . . . o-o o 29 . . . 28 . . . . . . 3 . . . 2 . . . 1 . . . ...where x, y, and z are labeled GND, SID, and VCC, respectively. The GND, SID, and VCC "holes" are used to configure the slot number using simple binary encoding, where GND is logical zero, VCC is logical one, and SID (for Slot-ID I guess) determines the current bit state (one or zero). Notice the four rows of GND, SID, VCC triads; each row is equivalent to one bit position in the slot number, the bottom row bit position 0, the top row bit position 3. This gives a total of four bit positions, or 16 possible slot numbers. To encode a slot number, you need to connect an SID row to its corresponding GND or VCC row. For example, the diagram below shows the configuration of the slots in my cube's back-plane (you'll have to look very closely to see the actual connections):

    SLOT #6 SLOT #2 SLOT #0 SLOT #4 BIT 3: o-o o o-o o o-o o o-o o BIT 2: o o-o o-o o o-o o o o-o BIT 1: o o-o * o o-o * o-o o o-o o BIT 0: o-o o o-o o o-o o o-o o ... Now on with the procedure:
  5. 5. To reconfigure slot #2 as slot #0, cut the trace between SID and VCC for bit position 1 (see * o o-o * above) and connect SID to GND on the same row. I used the SIMM removal tool supplied by NeXT in the 040 upgrade (talk about multi-purpose) to cut the trace! Very gently, scrape the solder off between the two holes. Take a paperclip, shape it to fit between the holes in SID and GND, and trim it down to an even 1/4 inch (perfect fit)! That's all there is to it. If for some reason you ever want to revert to slot #2, just remove the paperclip from GND-SID and reconnect it to SID-VCC.
  6. 6. Now put the cube back together. First, re-install the back-plane using its three connecting screws, then snap on the plastic plates, and finally insert the power-supply housing and secure with its two screws. At this point the cube is ready to take on the two system boards (it is up to you to determine where/how you want to use the two boards; I'll explain how I used mine) ...
  7. 7. I installed the 68040 in the original slot #0 and the 68030 in the reconfigured slot #0 (previously slot #2). The 68040 was used as the main processor board. I connected the 660 MB drive, the OD, and the monitor to it.

    NOTE: Before beginning the procedure, I went into the NeXT Monitor on the 68030 and disabled the Sound out, SCSI tests and verbose test mode and enabled serial port A as a console terminal. I also made "en" the default boot device. I setup the 68040 as a boot server and taught it about the 68030 (which took some time in getting it setup properly).

  8. 8. I connected the 68040 to the 68030 using a thin-ethernet cable and I booted. First thing I noticed was that the 030 timed-out a couple of times waiting for the 040 to tell it to boot. But after the 040 was up, the 030 booted nicely.
That's all folks. Hope all this made some sense and people find it useful.

Comments:

UPDATE TO PREVIOUS ARTICLE:

To clear up some misunderstandings with the settings in the "p" command of the NeXT monitor (these settings are only required for the system board that doesn't have the NeXT display monitor connected):

  1. 1. Sound out test must be "no"; the boot process will not proceed if the monitor isn't connected to the board and this is set to "yes" (the sound out tests will fail, aborting the boot procedure).
  2. 2. SCSI tests should be "no" if you don't have SCSI devices attached to the board (SCSI tests will fail otherwise, aborting the boot procedure).
  3. 3. Verbose test mode must be "no" for booting from the network. If set to "yes", the boot process will timeout waiting for a BOOTP and you'll be left in the monitor with no means of restarting the board (except pulling the power plug)! This is probably true also for booting from an OD that hasn't been inserted (assuming the OD was attached to the board).
  4. 4. Allow serial port A as alternate console if you want to view the boot process (for problems and peace-of-mind).
  5. 5. Other settings were not modified from their factory defaults or had no effect on the procedure.

Subject: L10. How to expand DSP memory?

The Speech Recognition Lab at San Francisco State University has developed a DSP memory expansion board for the NeXT computer that provides the maximum memory supported by the DSP56001 processor. We are now offering this board to those whose are interested in high-performance custom DSP development.

Note: Because we've organized our memory as three separate (non-overlapping) banks (X, Y and P) of 192KB apiece, none of the DSP memory image functionality provided by NeXT with its existing 8K base configuration, or its 96KB DSP expansion module is supported. While we cannot guarantee that every existing DSP application ever written will be plug-and-play compatable with our DSP expansion memory, we are not aware of any existing applications that use the image functionality. The MusicKit, and demo programs that use the DSP, such as Mandlebrot and ScorePlayer, work fine with our memory module.

Subject: L11. How to boot a NeXT without a monitor?

[From: The Onyx Kitten ]

The procedure is to just touch pins 6 and GND on the DB-19 NeXT monitor out with a 470 Ohm resistor (450 is the actual resistance, but 470 ohms is more commonly found in resistors). Pin 6 is the power sense, and pins 13-19 (and the DB shell) are the GND. Just say "pin 19", it may be easier. There's a pinout diagram of the DB-19 in the NeXT Users Reference Manual.

If you have an old Cube, the power supply needs to have more power drawn from it than an 030 (and 040?) board uses to stay on. So: On the DB-19, attach a Power Resistor (20 Ohm, at least 20 Watt) between pins 12 and GND. (Pin 12 is -12V, pin 13 works well for GND). Then just "touch" the 470 ohm resistor as described above, and you're set. The 20 Ohm resistor draws an old 030 running monitorless in an old CUBE), but it isn't necessary - just don't touch it (*HOT!* ;-)

To power off, type "halt -p" as root on the machine (either through a terminal connected to port A, or over the eithernet connection).

Also, you have to have the Rom Monitor settings done correctly. The important ones are:

Wait until keypress? N Sound out tests? N Port A as alternate Console? Y (if you have one, it's nice) Verbose mode? N (I think this may need to be N to work, don't remember).

Editor:

[email protected]