New - Amiga Romulator for A500 - A600

[Honey Badger]

with both LEDs working & being able to see its output via TLL adapter, was pretty well convinced the romulator itself was fine

and the Amiga itself being MOSTLY ok (my pcmcia interface being flaky), wouldn't have been too terribly surprised if something relating to the reset might have been wonky (although, that would probably create even bigger problems)

but yes ... quite pleased this is working -- and thanks for all the help/suggestions

[cuba200611]

Hello, this is my first post here. I just ordered a Romulator for an Amiga 600 that I recently got.

I have a question: Will it physically interfere with any fast RAM expansions or accelerators, besides the Furia, which it does physically interfere with? I currently do not have any such expansion installed, but I do plan on buying either a fast RAM expansion or an accelerator in the future...

EDIT: Is it possible to add an additional socket on top of the Kickstart socket before installing the Romulator such that there is enough clearance for something such as a Furia yet is low enough that the top half of the case (with keyboard included) will still fit?

[cdh]

I'm wondering if anyone else has experienced a red screen reboot loop (with flashing power LED) after the (68000) Amiga with Romulator has been running for a while (a few hours). I have two NTSC Amiga 2000 computers. One is rev 4.4 and the other is rev 6.3. Both have been recapped. One has had its power supply recapped. I have three Romulators (two A500/2000 and one A600). I've tried all combinations of the above and see the same thing on all of them. Sometimes it takes several hours of the Amiga just sitting there before the issue occurs. If I just do Ctrl-Amiga-Amiga, the red screen reboot loop continues. If I do a long hold of Ctrl-Amiga-Amiga, the Romulator menu will take over, load a ROM image and everything will be good again (for a while).

It doesn't seem to matter which ROM or OS version. I've see the failure with 3.1, 3.1.4, and 3.2 (beta).

If I leave the Amiga running a game which takes over the machine, it will not fail. With the Romulator installed, I've the memory test of AmigaTestKit for more than 24 hours without failure or reboot. I assume this is because it takes over the machine and runs from RAM.

If I replace the Romulator with an F2R16 flash chip, an original ROM, or Hyperion Amiga 2000 3.1.4 EPROM (27C400?), both Amigas are very stable. I've left them on for days without issue.

I've done some experiments to try to pinpoint the cause. One thing I noticed is that the WE# coming into the SRAM part is less than 3V. Watching it with the oscilloscope, it will sometimes dip down to 2.6V. I added a pull-up to 5V on that pin, but it didn't seem to make a difference, other than eliminate the dipping. The next thing I tried is a 0.1uF cap on 5V right next to the SRAM part. Didn't make a difference. I then tried a 220uF cap on the 5V coming in to the Romulator at pin 22. Didn't make a difference. I wrapped the entire Romulator in kapton and covered with grounded copper tape and it still didn't make a difference.

I'm pretty sure the SRAM is getting corrupted, but don't know how. I wrote a program that will repeatedly read the ROM address and compare against the expected ROM image. I will sometimes see it report corruption before the Amiga takes the first Alert which sets off the red screen reboot cycle.

I also have an Amiga 1000 where I've seen the red screen reboot loop problem with the A600 Romulator. Since that is a non-standard configuration, I'd like to focus on the two Amiga 2000 systems with problems.

[Matt020]

How did you get a hold of Amiga OS 3.2 beta??

[cdh]

Originally Posted by Matt020

How did you get a hold of Amiga OS 3.2 beta??

I am a beta tester and will also be purchasing licenses for it when it comes out.

[patracy]

Has anyone installed one in a 2000 with a megachip? I've used some sockets to rise over the megachip. I have a rev 4.4 board. Also where should I connect the reset? R201 is not in the same location as the videos. It's mounted further back and to the left from where the video places it. Also it's mounted transversely instead of longitude.

[cdh]

Please post a photo of your board. My Amiga 2000 Rev 4.4 has the resistor mounted with a longitude orientation near the floppy connector, so it's a bit of a surprise to learn your 4.4 has it mounted with a transverse orientation.

FYI, in the photo, you see my KBRST signal attached to a board Via instead of R201. I found this Via by continuity test as connected to the top lead of R201, and felt that the connection looked cleaner that way.

[patracy]

I had a brain fart and mixed the two (transverse/longitude). Mine is oriented that way as well. I've been foggy since time change. (Had to work and my sleep schedule is messed up)

[sbartley]

Originally Posted by Huxley_D

Hi everyone!

I was fortunate enough to snag one of Kipper2k's neat Romulator boards (purchase from Amiga on the Lake) to drop into my Amiga 2000 (Rev. 6.2). After many years of steady effort, my A2000 is pretty well upgraded, featuring an Ethernet card, Commodore RAM board, GVP SCSI board (hooked up to a SCSI2SD adapter I boot from), Individual Computers FlickerFixer board, and (the crown jewel) a Progressive Peripherals "Zeus" 68040 CPU upgrade running at 33MHz. It's a beastly machine, and I've been itching to add the Romulator since it's been sitting unopened on my desk for weeks.

I took the whole machine apart today and got the Romulator installed, after prepping the microSD card with a bunch of fully-licensed ROM images (including the DiagROM, and a newly-licensed Kickstart 3.1.4). When I boot the machine with the Romulator, it works great - I can select my ROMs, run the DiagROM, etc. - no issues there. I've also reinstalled the Ethernet board, RAM board, GPV SCSI board, etc., and they don't seem to have any conflicts.

HOWEVER: if I also replace the Zeus '040 board, I get nothing - the machine powers up (fans, power LED, etc.) but other than that, I cannot get any response whatsoever onscreen, and (based on the lack of floppy activity and/or Romulator menu-music) it doesn't seem to be doing anything at all. Removing the Zeus board instantly gets the system working again, but without the amazing speed improvement the Zeus board offers (and which I'm not exactly looking to give up).

Any ideas or suggestions here? I really want this to work!

Thanks,

Huxley

I have the same problem with the A2620 board in my Amiga 2500. When I take it out, the Romulator works fine. I put the board back in and lights, but no action. It is NOT a 68040 issue. It has something to do with the Romulator interaction with the co-processor port. However, without any documentation, I have no idea if what else to do to make it work.

[cdh]

I don't have access to either of these accelerators, but my guess is that they treat _RST as an edge signal rather than level signal. The Romulator appears to hold the CPU in reset until it's done loading the SRAM from the MicroSD. If the CPU is off doing fetches during this time, it's sure to get corrupt instructions.

The only thing I guess might work is if the Romulator code pulsed _KBRST instead of just driving the signal low. I don't know about the developer's availability, as I think he is very busy on another project now. You might have more luck making a simple circuit to drive the A2000's _KBRST using pulses from a 555.= (when the Romulator drives _KBRST low).

[mkstr]

Originally Posted by cdh

I don't have access to either of these accelerators, but my guess is that they treat _RST as an edge signal rather than level signal. The Romulator appears to hold the CPU in reset until it's done loading the SRAM from the MicroSD. If the CPU is off doing fetches during this time, it's sure to get corrupt instructions.

The only thing I guess might work is if the Romulator code pulsed _KBRST instead of just driving the signal low. I don't know about the developer's availability, as I think he is very busy on another project now. You might have more luck making a simple circuit to drive the A2000's _KBRST using pulses from a 555.= (when the Romulator drives _KBRST low).

This is correct - the Romulator holds the CPU in reset to ensure that the bus is released so it can program the SRAM. The menu and the selected Kickstart ROM are no different in this respect (the menu is just a custom ROM, effectively).

Since the aim is to keep the bus idle it might be worth trying to assert /BR at the same time as the reset (use a pair of 1N4148 diodes with the cathodes pointing towards the Romulator reset signal to keep BR and KBRST separate), although the Amiga doesn't use the bus request logic so an accelerator card might ignore it anyway.

Do any of these troublesome accelerators have schematics available that I could take a look at?

Mike

[mkstr]

Something else that would be useful is if someone with an accelerator could wire up to the console port on the Romulator (TTL USB to serial adapter required, and a couple of wires soldered on). From here you can force a particular ROM to be loaded even if the menu isn't working, which would help determine whether the problem is due to a hardware or menu compatibility issue.

If anyone wants to try this let me know and I'll send instructions.

[Ledfoot]

Originally Posted by sbartley

I have the same problem with the A2620 board in my Amiga 2500. When I take it out, the Romulator works fine. I put the board back in and lights, but no action. It is NOT a 68040 issue. It has something to do with the Romulator interaction with the co-processor port. However, without any documentation, I have no idea if what else to do to make it work.

Dammit! I have one of these arriving today to put into my 2500 with A2620 card! grrr.

[cdh]

Originally Posted by mkstr

Do any of these troublesome accelerators have schematics available that I could take a look at?
Mike

The Romulator in my Amiga works fine with the TF534 installed in the CPU Slot.

sbartley wrote that he has trouble with the Romulator and the A2620. The A2620 schematic is available HERE.

I really don't recommend investigating further without someone who can probe the A2620. The _RESET signal from the CPU slot edge connector goes straight into several PALs and any one of them might be acting on it based on an edge detect only.

[Ledfoot]

Nevermind, CDH beat me to it...

I have an A2620, but waiting on new ROMS for it so it'll even work with a KS>1.3... I also only have one of those crummy little pocket O-scopes so don't know how much I could really do to help you probe... But if there's something I can do to help, let me know.

[cdh]

Ledfoot: So long as your pocket O-scope has two inputs, I think that would be enough. My thought (mkstr please correct if you're thinking something else) is that if you probe the _KBRST signal out of the Romulator and compare that against the RESET signal into the MC68020 (_CPURESET in the schematic) then they should match. If the 68020 is coming out of reset while _KBRST is being held by the Romulator, then that's a pretty clear sign that the A2620 is ignoring RESET or only paying attention to an edge.

[Ledfoot]

I'll have to pull the o-scope out and check. Haven't used it in years. The UI is unbelievably clunky to use since the hardware was originally designed to be an MP3 player! lol

Waiting on the V7 roms for the A2620 before I can run that, so maybe next weekend or the weekend after I can do a little probing around... If mkstr wants to give me other instructions on how to set up that console (pretty sure I have the connector thing he's talking about, sounds like what I use to program the firmware on gotek boards...) I can try that too...

[Ledfoot]

Ok, just checked my pocket o-scope. 1 probe only

[cdh]

Sorry, I don't think you'll be able to detect what's going on with with just one probe.

[patracy]

Has anyone gotten the romulator to work with a GVP 030 accelerator? I only get a blue screen when I try to select a rom. I've removed J9 on the GVP card to get it to at least give me the romulator selection screen.