View Full Version : ISA POST status reader and IRQ tester

October 24th, 2012, 11:29 AM
Is there a need for a kit of this, or interest?
I rate this as something simple I have the schematics for this practically done.

October 24th, 2012, 01:52 PM
I'm interested, in principle.

You are probably aware that ISA and PCI POST diagnostic cards are sold online from 99cents upward.

On Ebay today (http://www.ebay.com/sch/i.html?_nkw=pci+isa+post+card), some examples.

Others on this forum have had mixed experience (in my case, failure) with one or more of these cards.

There is definitely a demand for such a product, but you would have to consider whether the cost/benefit of a kit would be more attractive than trying 3 different online products and still having change from $20 after postage.

When you say "simple", what is the parts list like? Does it run software/firmware?


October 24th, 2012, 02:19 PM
I would think so but also already have 2 that I rarely if ever use. Quite a bit more useful for older hardware when it's repairable vs the newer pci motherboards with surface mount everything and integrated components. Although I do think it's neat with the dual interface cards that plug into isa on one end and pci on the other. As Rick said, I think it's useful but also the cost might be prohibitive.

Actually one comment as well. The most useful part of the cards were really the descriptions made (documentation) that were helpful. That somewhat made or broke my opinion of the different cards out there.

Another cool feature would be making an external output panel (although I know it's generally a temporary use card) but if one could mount the display on the case it'd be neat.

DOS lives on!!
October 24th, 2012, 05:33 PM
They're readily available, and I've got a few vintage card testers too. But in interest, what do you have idea wise? The newer card I have already has an external output display that plugs into the main card.

October 24th, 2012, 09:58 PM
The ISA card I have is manufactured by JDR Microdevices and it's a jumperless one that's always worked for me on everything.

However, a cheap one that works better than ebay ones that aren't being shipped from China I wouldn't mind buying. I'm willing to pay a few bucks more to not have to wait 2-5 weeks for shipping and instead wait 2-3 days with US Postal Service.

October 25th, 2012, 07:29 AM
I have two, neither are similar to what you find on ebay. One has a rotary dial where you can see the BIOS codes, plus see a few other things but the other card is a nice 16-bit ISA card that displays all the DMA and IRQ spaces. I want to make more of that card but it consists of four GAL chips.

October 25th, 2012, 12:17 PM
I was thinking of BIOS POST status in Hex, most ISA based systems have their BIOS spread over 4 different addresses.(the difference between a PC and a Compaq for instance)
Segment Led
Besides that testing IRQ lines is rather simple and only requires a load on their respective lines.

For testing card i was planning to keep it on a 8-bit card.
Schematic I shall post this weekend.
I am not gonna produce this board i am just gonna make it public available for those with the skills and tools.(most of them would already have such a card.)

October 25th, 2012, 12:26 PM
So essentially one card that will display IRQ, DMA, clock, and the basic voltages, plus have a multi-segment display that will dispaly the BIOS POST status codes with a rotary switch (or dip switches) that selects between the different address ranges for the different BIOS types used.

October 25th, 2012, 08:12 PM
Yes, NeXT that is exactly what i designed.
A tool every self respecting PC repairmen already has and actually has some use.
I am not sure if i should make a frequency counter on it or a cycle counter till PIT kicks in?

October 25th, 2012, 09:57 PM
I find the switches interesting, mine auto-switches between addresses so I don't have to set anything, Plug-N-Play I guess you could say.

October 26th, 2012, 01:36 PM
here is one with a external display

DOS lives on!!
October 26th, 2012, 03:22 PM
here is one with a external display
That is the exact slot tester that I have. That external display comes in handy when other cards are blocking the onboard display.