EII and HxC - Can't get past "Loading" screen on Startup

[ryansupak]

Hi, I bought an EII HD+. The floppy drive was shot and I decided I didn't want to deal with the "vintage" HD at all. (Otherwise, the unit looks to be in very good shape.)

So, I got an HxC. I set the disk to Emu Shugart, put the HxC config file and emuiios.emuiifd.hfe (thanks ESynthesist) on the card, and set the Drive Jumper to "Drive A\ID0".

I replaced the original 34-Pin floppy cable (total of 3 connectors) with a "straight" cable (total of 2 connectors) and hooked the HxC up. I rewired one the original drive power cables to the smaller connector. (The HD and Floppy Drives were removed entirely. "Retro" data storage isn't why I bought the unit) ;)

Then, I crossed my fingers and powered the unit on. The HxC sprung to life and I selected the emuiios file. Nothing further happened on the HxC, and the Emulator II displayed the message:

Code:

***Emulator II***
Boot In Progress

After this, I tried rebooting with the file already selected, rebooting with an EII file instead, and I tried messing with the jumpers. I even disconnected the "new" floppy cable entirely and plugged the old cable back in with nothing hooked up to it.

Nothing I do will get the Emulator readout to change its message from "Boot In Progress" or  get the HxC to do anything.

I'm open to any suggestions -- but as I just moved to a new location, plugging the original storage hardware back in is not an option. It's either in a junk-box or lost. If it's relying on some kind of resistance load from the old Floppy and/or HD to proceed in the Boot Sequence, I'm going to have to find some way to "fool it". (I would think this is doable, as I know that these old floppies and HDs failed pretty routinely.)

Finally, I do have a copy of the Service Manual. Unfortunately I can't find anything about the Startup Sequence, at least not yet.

Thanks for any suggestions.
rs

[ryansupak]

In researching this I've learned some interesting stuff.

Here is a detailed technical article on Floppy Drive cables: http://www.nullmodem.com/Floppy.htm

It looks as if I *may* need to fake out the Emulator II with a dual floppy drive cable. Luckily they are readily available on eBay, and when the time comes to mount the HxC I can use a 34-pin male header and a round floppy extender cable to lengthen it a bit.

rs

[esynthesist]

You may have to use another boot rom, I'm not sure.
The boot rom in the EIIHD is specific for a HD version. But one would guess that if it doesn't see a proper working HD within reasonable time, it should check the floppy (HXC) after a while.
Unfortunately I don't have a HD version, so I can't test it...

A standard EII and EII+ can work with only the HxC installed (without any other floppy drive).
The floppy ribbon cables can be any kind of 34 pin cable on the market, either twisted or untwisted, with one or more connectors. It's just a matter of setting the jumper correct (ID0 or ID1) on the SD HxC.

[ryansupak]

esynthesist: Firstly, thanks for all the hard work you've done for this community. <3

When I first got the unit and the Floppy and HD were intact, the unit would remain idle until a floppy disk was inserted. When a Floppy was inserted, the Emulator II display would say something to the effect of "Loading, this may take a while". But, it would never finish. I also read that the unit will *not* boot off the HD, only the Floppy though I can't verify that behavior.

What I'll do next is download the EII-HD rom from emxp.net and try to "time out" the load process.

Thanks,
rs

[ryansupak]

(FYI www.emxp.net appears to be down as of Sunday, 27 November, 4:00 PM GMT.)

rs

[ditabeardmemo]

Ryan, so what you're saying is the Emulator II+ HD that you own never booted prior to your installation of the HxC, right?

Your information about booting from the hard drive is incorrect... the EII+ HD most definitely will boot from a working hard drive.

It sounds to me like you have a faulty EII.

[esynthesist]

(FYI www.emxp.net appears to be down as of Sunday, 27 November, 4:00 PM GMT.)

Thanks for the notification.
I just checked my account, but from that perspective everything seems OK, i.e. the alias www.emxp.net is still mine and still registered to forward to the hosting site.
But in practice, the alias seems indeed not to work anymore.
It seems to be a general problem; other customers of my internet provider/hoster are complaining too.
I hope it will be resolved by them soon.

The EMXP website can of course still be accessed through its native URL: http://users.skynet.be/emxp

But I don't have ROM images on my website; ROM images are hosted on the Yahoo Emulator-II group; the HD one is not available, but the non-HD ones are.

[ryansupak]

Guys, thanks for that info.

I'll look into installing the non-HD ROM on my machine.

rs

[ryansupak]

Before going that route I am working through this E-Mu troubleshooting document. It sounds like my problem is somewhere in here.

http://www.emulatorarchive.com/assets/PDF/EII%20Diagnostics%20Manual.pdf

[ryansupak]

Swapped out both Z80s (main and scanner), along with their clocks, their PIOs, and the DMA chip. It looks like the main Z80 clock is receiving power but *not* pulsing which likely means a problem in the clock circuitry.

I've also ordered a new scanner and main EPROM, as well as a main debug EPROM to be used with a Terminal Emulator (These EPROMs are about USD $12 apiece burned by Doug at ealnet).

Even if I don't get it fixed I'm learning a lot, plus it keeps me off the street
rs

[ryansupak]

(I'm mostly posting my progress here as documentation for anyone else who might ever come along with a similar situation.)

Got clock circuitry and Main Z80 working properly together by reseating everything.

My system has the HD upgrade but I'm bypassing the HD (and the Floppy) entirely. IC128 on the "non-HD" version is a Z80 SIO/2 IC, as I've learned from the Service Manual. (This is an extremely common chip used as a disk controller.)

The HD-upgraded Digital Board has a gold-plated IC connector in place of IC128. Connected to the IC128 socket is an HD controller board on a riser, and a ribbon cable which connects to an additional SCSI controller board about 12" to the right (I learned that these (2) boards were additions, from the "how to upgrade EII to EII+HD" document hosted on the EII Yahoo Group.)

But, as luck would have it, the first IC on the riser board is the very same Z80 SIO/2. So, I removed it from the now-extracted riser board and stuck it in socket IC128. Based on oscilloscope readings, this appears to be functioning properly.

My understanding is that, once I've got the "original" EPROM chips in place as opposed to the HD ones, I should have a machine that's electronically identical to a non-HD Emulator II. At this point my guess is that the HD EPROM is looking for an HD, and not finding the circuitry at all, and so it doesn't know what to do next. I'll know for sure once the new EPROMs arrive in a week or so.

rs

[esynthesist]

I think you are the right track.

I've investigated this "downgrade" from HD to non-HD a few weeks ago also... just on paper though because I don't have an EII HD. But  I tried to help someone who has wants to do the same downgrade. And I came to the same conclusion as you do.
However I don't know the results from the guy I tried to help, I think he didn't start the downgrade project yet.
So... yes, please keep posting your progress here !
I'd really like to know if it will work once the non-HD eprom is installed.

BTW: it would be nice if you (or someone you know) could read out the HD EPROM and upload that binary image to the Yahoo group. We are still missing that version of the EPROM !

[ryansupak]

I'll definitely post-back once I know for sure. The EPROMs are on their way to me so I'll know very soon.

Also, I'm going to have the same person who burned the new images for me, extract the EII+HD EPROMs from my "old" chips. Once I have these .BIN files, I will let the Yahoo Group administrator know so he/she can post them alongside the other EPROM images that have been collected.

rs