A3000 + a3640 = keyboard issues

[heymanj]

Howdy,

I've been the owner of an 16MHz A3000 desktop for many years (bought used in 1995 after I had issues adding the 2.04 ROM to my original A1000).  It's been expanded with an A2065 (Ethernet), a DKB128 (128MB of SIMM memory), a ULowell graphics card (not used), as well as several scsi drives.  The thing I've always wanted to do is put an a3640 (25MHz 68040) in it.

I've recently purchased said a3640 on eBay - version 3.1.  After changing all the necessary jumpers on the motherboard, I booted the box.  Everything came up roses, until I tried to enter my userid/passwd for Genesis TCPIP (I have that in my initial startup).  I was able to type the first two characters of my userid and then the keyboard refused any more input and kept sending the 2nd character repeatedly thru.

Mouse still works fine, so I've been able to run gui based apps to see that the a3640 is recognized, but am unable to type anything in  :-(

The keyboard was usable prior to the upgrade, and is on a KVM where it is successfully working with a p3 based system.

I have not reset the A3000 back to 16MHz to retest the keyboard because taking the a3640 out requires complete disassembly - and would rather avoid that if I can...

Any thoughts/suggestions :-?

Thanks!

jerry
       //  Jerry Heyman      | "Software is the difference between
      //   Amiga Forever :-) |  hardware and reality"
  \\ //    heymanj@acm.org   |
   \X/     http://bellsouthpwp.net/h/e/heymanj/

[Matt_H]

Using the 3640 in the 3000 desktop was never an officially endorsed solution by Commodore due to heat issues - it's not too safe to run without a heatsink, and units with a good one have trouble fitting physically. I'm assuming you have one with a tiny heatsink with integrated fan? Hopefully things aren't getting too hot.

Anyway, I'm afraid that disassembly is going to be pretty likely. The 3000 has what seems like a gazillion jumpers that need to be set for CPU cards. Make sure those are all correct. Also, what are your Ramsey and DMAC versions? 7 and 4, respectively are best for a 3640. I couldn't get one working in a 3000T with Ramsey 4 and DMAC 2.

But there's a slight chance you don't need to take everything apart. It sounds like your keyboard is plugged into a KVM and a PS2->Amiga adaptor. Try without the KVM. Get as direct a connection as possible to eliminate other possible sources of trouble.

[amiga_3k]

On the direct connecting I totally agree with Matt_h. I even add that it would be wise to use the original Amiga keyboard (if still available and working).

I ran an un-modified A3640 in my A3000D/16 for a few years without any problem. It was also fitted with the DKB memory board with a PicassoIV with TV-tuner. Other heat-producers inside the case were two SCSI harddisks. What I did do when I got the DKB3128 was shifting the 1 MB FastRAM chips (located underneath the drive-area) to the ChipRAM area (located in the ZORRO III area). That took a little heat out of the drive-area.

When I fitted the A3640 (after the machine came from the shop that modified the main-board so it could use the 3640) I took it apart again to make sure the internal SCSI cables were as short as possible and routed in a way that allowed maximum air-flow from underneath the drive-bays towards the PSU.

To keep things as cool as possible make sure the floppy-drive is in its original position (right above the accelerator board). As it's less used than any harddisk it should remain cooler, alowing better heat radiation from the accelerator.

Another thing... Have you tried starting up the machine without all the extras? Might be a software issue.

[Noster]

Hi,

as already said, I would also try to use the original Amiga keyboard. Which adapter do you use to attach the PC-keyboard to your Amiga? Does it require any software to run? Maybe here is your problem. Or any other program you start during booting is unable to run correct on an 68040 and produces the trouble.
Go through the early boot menu and try to boot without startup-sequence.

I hope you have installed Kickstart 3.1? In any other case you get into trouble with an A3640.

Noster

[heymanj]

Many thanks for the suggestions.  Not looking forward to taking it all apart again, I tried the easiest suggestion - taking the A3000 off the KVM.  Bingo!  Solved the problem.

Now I only will have two keyboards, two mice, and one monitor on my desk :-) :-(

As for the heat generated by the accelerator, I was thinking of buying a case fan, hooking it up to the spare 4pin power adapter (only have one drive in the machine), and trying to rig it to blow across the accelerator.  I am definitely open to suggestions as ya'll obviously have much more experience with this than I do.

Thanks again!

jerry
       //  Jerry Heyman      | "Software is the difference between
      //   Amiga Forever :-) |  hardware and reality"
  \\ //    heymanj@acm.org   |
   \X/     http://bellsouthpwp.net/h/e/heymanj/

[motrucker]

Put a real CPU fan on it! It will make a huge difference! The case fan will make little if any difference in cooling the '040 - these things get HOT.

[A3KOne]

I would overclock it to 31Mhz.  On the A3000, there are motherboard timing issues and the A3640 does not do well at 25Mhz.  OC/d to 31 it runs great and with a cpu cooler it has no problems.  Overclocked, it will do a fair job of playing mp3's.

[heymanj]

motrucker wrote:
Put a real CPU fan on it! It will make a huge difference! The case fan will make little if any difference in cooling the '040 - these things get HOT.

Got any recommendations?  I know that there isn't much clearance/room for a CPU fan, and I'll probably have to find one that uses paste to hold it on - I didn't notice the ability to clip on a CPU fan.

jerry