Network card typically uses DMA. Copy a file from a network share to your local drive, md5sum it.

Or play a clip through Soundblaster card.

I don't have a soundblaster, and while I have a NIC sitting on the bench, I haven't tried it out yet.

Scott

smbaker wrote:

When you run your champions of krynn test, are you just leaving it at particular stage of the game, or are you doing something else? I had mine running in "demo mode" (where it shows various cut scenes, goes through a battle, etc) and after about four hours it exited with a "runtime error 200", which is a turbo pascal division by zero error. I'm not sure if that is a corruption issue or just a bug in the game for leaving it in demo mode for an extended time.

As for more details on the terminator board, I have a write up at http://www.smbaker.com/diagnosing-xi-8088-stability-issues

Question about your active terminator:

What are the pin connectors for on the edge of the card? This gets +5v from the ISA bus itself, right?

Is that simply for checking output voltage, as you suggest in your writeup?

OSHPark required me to order 3 of the active termination boards for $34.50. I only need one. If anyone else is interested in one of the remaining two, PM me and I'll toss it in the mail for $10 + shipping. I'm in the U.S.

Hopefully that doesn't violate any policies here.

keenerb wrote:

smbaker wrote:

What are the pin connectors for on the edge of the card? This gets +5v from the ISA bus itself, right?

Is that simply for checking output voltage, as you suggest in your writeup?

Correct. The header on the top of the board is 5V/GND, and the header on the side of the board is Vterm/GND. I used them to setup the board on the bench. I don't have them connected to anything while the board is installed.

My Xi 8088 is still running Ultima IV, for what it's worth. No apparent problems.

Scott

With a lot of ISA cards, I presume?

Yeah, I'm running Ultima IV with my full set including the problematic CP/M coprocessor.

Still looking good, Smbaker?

I rebooted it to fool around with some other things, but it was working fine when I did.

Scott

fantastic.
ISA bus terminator: Does it actually need to "terminate" the bus, i.e. be at the farthest slot from the xi 8088?

I passed this development on to Sergey, if we determine this to be an adequate stability fix he'll update the backplane to include active termination...

I don't know that it needs to be on the farthest slot, though that's more-or-less where I have mine. I do think adding footprints for terminating resistors on the backplane is probably a good idea and a very simple thing to do. For example, this advantech backplane on eBay has numerous resistor pack footprints:

http://www.ebay.com/itm/Advantech-6-ISA-PC-Bu … 8l3Wn77rClnfdRw

Oh, and Duh! I just realized that I could have (and should have) installed SIP sockets into my terminator board, then I could have easily experimented with alternate resistor values.

Scott

Anyone have any new developments? I've been working on designing an ISA speech synthesizer card, and haven't done any more investigation of Xi 8088 stability. I would like to spend some more time on that, perhaps come up with that benchmark that exercised IO, DMA, and Memory.

Nope I have been waiting for my terminators to arrive. oshpark isn't exactly speedy.

smbaker wrote:

I don't know that it needs to be on the farthest slot, though that's more-or-less where I have mine. I do think adding footprint […]
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I don't know that it needs to be on the farthest slot, though that's more-or-less where I have mine. I do think adding footprints for terminating resistors on the backplane is probably a good idea and a very simple thing to do. For example, this advantech backplane on eBay has numerous resistor pack footprints:

http://www.ebay.com/itm/Advantech-6-ISA-PC-Bu … 8l3Wn77rClnfdRw

Oh, and Duh! I just realized that I could have (and should have) installed SIP sockets into my terminator board, then I could have easily experimented with alternate resistor values.

Scott

Hey Scott, which resistors did you use on your active terminator? Mouser and others give me a lot of options like bussed/ladder/etc. that I'm not familiar with...

And what was the rating on the adjustable potentiometer?

Also, are you using your new buffered memory alongside the ISA terminator, or the standard parts?

you want bussed, not laddered.

BloodyCactus wrote:

you want bussed, not laddered.

Thanks, that's what's sitting in my shopping cart right now; I just bought the same type I bought for the xi8088 itself, only different pins and different ohms...

I don't think it matters too much what trimmer pot I get as long as it's not too high, since I'll simply be adjusting it to whatever gives me 2.7v...

Got my boards from OSHPARK today, my components will be here Friday.

I'm excited about (hopefully) having a fixed and dependable system this weekend...

The pot I'm using is a 5K Bourns 3362 series. I believe that's half watt. In retrospect, I may have chosen a 10 turn pot instead -- the adjustment is kinda logarithmic, and it's really touchy once you get to the > 2V range on voltage. Single-turn pot worked well enough though.

Yes, bussed resistors is correct.

I'm using the original RAM, though it did also work with my buffered RAM modules. I'd be curious if your Lo-Tech board will work, with the Xi 8088's RAM removed, and the bus terminator added.

Scott

I am as well.

I ended up grabbing a single-turn 10k resistor, so it's gonna be SUPER hard to tweak this sucker to 2.7v I'm afraid.

keenerb wrote:

I am as well.

I ended up grabbing a single-turn 10k resistor, so it's gonna be SUPER hard to tweak this sucker to 2.7v I'm afraid.

You could try increasing the other resistor. The formula in the LT1118 data sheet is:

Vout = Vfb (1 + R1/R2) + Ifb*R1

Vfb is 1.225V

With R1 being the fixed resistor and R2 being the pot. My R1 is 240. Measurement shows that I have adjusted my R2 to about 204 ohms, which according to the formula is somewhere in the neighborhood of 2.64 V. In retrospect, a 1K pot probably would have been ideal. Perils of doing the math after I constructed the prototype...