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SB 16 on XT

evildragon said:
I'll give IRQ7 a try... I do have IRQ2 for cascading..

(and i don't have VOCPLAY.. check my backup from the previous page, that's all I have to work with)

wait a minute, I can't use 7 either, and according to this IRQ5 is for LPT2..
Click to expand...

That's an AT or later -- see how it goes up to 15? Doesn't apply to you. Trust me, your hard drive is using IRQ5. You can't stomp on the IRQ your hard drive is using and still expect to use the hard drive.

LPT1, on the other hand, is NOT in use if you don't load your zipdrive driver. So it's ok to put multiple devices on a single IRQ as long as you'll never run any of them at the same time.

Change the SB16 to IRQ 2 or 7 and let us know if 8088flex works.

I have an original, bought-the-day-it-came-out Sound Blaster 16ASP. I still have the disks. Would you like me to image them for you and make them available?
 
Trixter said:
That's an AT or later -- see how it goes up to 15? Doesn't apply to you. Trust me, your hard drive is using IRQ5. You can't stomp on the IRQ your hard drive is using and still expect to use the hard drive.

LPT1, on the other hand, is NOT in use if you don't load your zipdrive driver. So it's ok to put multiple devices on a single IRQ as long as you'll never run any of them at the same time.

Change the SB16 to IRQ 2 or 7 and let us know if 8088flex works.

I have an original, bought-the-day-it-came-out Sound Blaster 16ASP. I still have the disks. Would you like me to image them for you and make them available?
Click to expand...
I think model 25's really do have 15 IRQ's.. While IBM classifies them as XT's (if you don't have the SX model), it has some features not found on the original XT's..

I tried setting the SB as IRQ 2, and then I get "General failure reading drive C:", then I tried 7, same thing (and now, same thing even with the way it is)...

My HD really is biting the dust.. For some reason, whenever it's asked for a massive transfer, it spazzes out.. Even trying to run Windows 3.0, it can sometimes do this.. I had a post a while back about it, it has funky bad sectors that are "random"... This is something that has been happening before I even put ISA cards in this computer...

(i've been looking for a SCSI card or something to put in the 25...)

--------------------------------------

ANYWAYS! :p VOCPLAY was on the 486 in the attic. Now I just need to convert my wave file into a VOC file, that is, presumably, small enough to fit in RAM? (does VOCPLAY rebuffer if it's too big?) I can easily edit my files...

EDIT: Nevermind, I got an editor that exports VOC.. however, VOCPLAY won't even run, it gives me VOC Driver Error 1.. I assume this is because it's not even loading ct-voice.drv, nor is it linking to it like it should.. How do you use VOCPLAY? And how do I load ct-voice.drv to work with it?
 
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Trust me, you don't have 15 IRQs. Your Model 25 uses an 8-bit ISA bus. You can't have those extra IRQs because they are physically not part of your ISA bus. Look at the pinout of a 16-bit ISA slot:

http://pinouts.ru/Slots/ISA_pinout.shtml

Notice that the extra IRQ lines are on the 16-bit portion.

An 8088/8086 system cannot use a 16-bit ISA bus, because they can only do 20-bit memory addressing, and 16-bit ISA requires 24-bit memory addressing. 8086 CPUs do however have a 16-bit datapath...so a proprietary 16-bit expansion bus may be possible, but I've never seen it.

I think the program you are running is just meant for AT class machines, and is not reporting the usage of your system resources accurately.
 
ok, so i'll keep it on IRQ2 as a safetey measure then...

while an ISA card can't handle the IRQ's, couldn't an on-board device use it however?

(i just used a different utility, Syschk, and it did report different IRQ's, ones that are more believable, and shows IRQ2 free.. though, it does list 5 as free also..)

(trixter: when I put the SB16 on IRQ2, and try 8088 corrruption via the zip drive, as the HD route still wouldn't work, the animation was actually fluid, but stops every 5 seconds, and the ZIP drive reads like crazy---so, even though the HD in my IBM won't budge for this, and even though the ZIP drive still is too much for it, it DOES move faster now..

EDIT: It's now working with the HD, the ribbon must have been loose all these years... But, with the HD, it now skips every 10 seconds, stopping for like 8 seconds, while the HD reads like crazy, sorta like the zip drive)
 
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Well, actually it is still not possible to have more than 8 IRQs on an 8086/8088 system, because those chips only have one interrupt controller that can handle up to 8 interrupts. The 80286 and above CPUs however, have TWO interrupt controllers that are cascaded (that's why you can't use INT9 on a 286, remember).

Does that help? :D

*EDIT* It seems that my understanding of this is a little off....I thought the interrupt controllers were built into the cpus, but apparently this is not the case. So, I can't really say for certain it is not possible to have more than 8 IRQs on an XT. I recommend locating the IRQ controller on your motherboard and looking it up online to confirm that your suspicions are incorrect.
 
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Anonymous Coward said:
Well, actually it is still not possible to have more than 8 IRQs on an 8086/8088 system, because those chips only have one interrupt controller that can handle up to 8 interrupts. The 80286 and above CPUs however, have TWO interrupt controllers that are cascaded (that's why you can't use INT9 on a 286, remember).

Does that help? :D

*EDIT* It seems that my understanding of this is a little off....I thought the interrupt controllers were built into the cpus, but apparently this is not the case. So, I can't really say for certain it is not possible to have more than 8 IRQs on an XT. I recommend locating the IRQ controller on your motherboard and looking it up online to confirm that your suspicions are incorrect.
Click to expand...

The 8086-based Model 25 does effectively have two "PIC"s (Programmable Interrupt Controllers). They are in a custom chip for the planar, so you wouldn't see any chips with "8259" on them. A diagram of the planar is at http://walshcomptech.com/ps2/m25.htm (but, as said, those extra IRQ lines are unavailable on the 8-bit bus).

There is even a way to query if the second PIC is present (which should be true for a 286 and above anyway). It is INT 15h AH = C0h (http://www.IBMMuseum.com/interrupts/INT15h/INT15hC0.html). Bit 6 of "Feature Byte 1" is set if present.
 
evildragon said:
so, should I use IRQ2 or not? If it has two PICs, how is it interfaced then, does it take IRQ2?
Click to expand...

I have the Technical Reference around for the Model 25 and 30 (8086 level) that shows IRQ usage, but I can't lay my hands on it at the moment...
 
Hmm...I'm not so sure about that. The relationship between the processor and coprocessor in XT systems is much different than in 80286+ systems. I am not sure that the 8087 needs an IRQ, but the internets seems to indicate that 8087s might use NMI.
 
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evildragon said:
I think model 25's really do have 15 IRQ's.. While IBM classifies them as XT's (if you don't have the SX model), it has some features not found on the original XT's..
Click to expand...

No, it only has 8. It has the same PIC as the original XT.

I tried setting the SB as IRQ 2, and then I get "General failure reading drive C:", then I tried 7, same thing (and now, same thing even with the way it is)...
Click to expand...

That sounds more like coincidence than the sound blaster. I would remove the sound blaster and see if you still have the errors. If so, it's time to boot Spinrite and let it try to salvage the drive.

EDIT: Nevermind, I got an editor that exports VOC.. however, VOCPLAY won't even run, it gives me VOC Driver Error 1.. I assume this is because it's not even loading ct-voice.drv, nor is it linking to it like it should.. How do you use VOCPLAY? And how do I load ct-voice.drv to work with it?
Click to expand...

Through an environment variable which I can't remember that the moment.

I'll image my original install disks for you and provide a link in a few hours. Once you get your hard drive issues sorted out, set the SB16 on IRQ 2 or IRQ 7 and try to install the software and see what happens.
 
Anonymous Coward said:
Trust me, you don't have 15 IRQs. Your Model 25 uses an 8-bit ISA bus. You can't have those extra IRQs because they are physically not part of your ISA bus. Look at the pinout of a 16-bit ISA slot:

http://pinouts.ru/Slots/ISA_pinout.shtml

Notice that the extra IRQ lines are on the 16-bit portion.
Click to expand...

While you are correct that 808x systems can't have more than 8 IRQs, it has nothing to do with the bus -- that's incidental. The real reason is that the programmable interrupt controller (PIC) only supports 8 hardware interrupt lines. In ATs and later, a second one was added, with IRQ 2 on the first chaining to IRQ 9 on the second. But that's independent of the slot width.
 
evildragon said:
(trixter: when I put the SB16 on IRQ2, and try 8088 corrruption via the zip drive, as the HD route still wouldn't work, the animation was actually fluid, but stops every 5 seconds, and the ZIP drive reads like crazy---so, even though the HD in my IBM won't budge for this, and even though the ZIP drive still is too much for it, it DOES move faster now..

EDIT: It's now working with the HD, the ribbon must have been loose all these years... But, with the HD, it now skips every 10 seconds, stopping for like 8 seconds, while the HD reads like crazy, sorta like the zip drive)
Click to expand...

Good, that means IRQ2 is free on your system, just like the 5160 I developed it on. Stay on IRQ2.

As for the pausing, it shouldn't be pausing THAT much... make sure you have as much system RAM free, and also don't run the original 8088_cor.zip, run the updated 8088flex player and sample .tmv files from the website. A good one to try is TRONDISC.TMV -- it's less than 4 MB and only 24fps.
 
Yes indeed, 2nd pic used by the math co-processor. Wow, I never got into all the fine details on all the IRQs before, I just knew it was always a pain to find enough for those sound cards, especially if you didn't have the high order IRQs available. (put studdering sound here).
 
evildragon said:
i was using 8088flex... i have 540KB freem memory when I try to run it.. i'll try the trondisc demo...
Click to expand...

Might also help to run spinrite on the disk -- if the disk is unhealthy, the kind of refresh spinrite does to an MFM/RLL disk might speed it up a bit.

BTW, if you or anyone is looking for stock Sound Blaster 16 install disks, I uploaded them here:

ftp://ftp.oldskool.org/pub/misc/SB16ASP

They're the complete diskette distribution from the Sound Blaster 16 ASP package, but don't worry about the ASP part, the DOS stuff should be the same... I used pkzip's volume label feature, so if you use command-line pkunzip you can use the same feature to restore the volume label of the disks (which I would recommend if you're going to try to restore from them).
 
chuckcmagee said:
I just knew it was always a pain to find enough for those sound cards, especially if you didn't have the high order IRQs available. (put studdering sound here).
Click to expand...

It's even more of a pain to try to write software for them ;-)

IRQ 2 was almost always free on any 808x PC. That's why the early Sound Blasters support it. Later sound cards were built for 16-bit ISA buses, which meant ATs and later, which meant that IRQ 2 was really a chain to IRQ 9 in the second PIC, so support for IRQ 2 went away.

For typical assignments, look here:
http://www.ltsw.se/knbase/misc/irq.htp
 
By the way, it may look like the AT-compatible assignments are listed out of order on the http://www.ltsw.se/knbase/misc/irq.htp page, but he was actually quite clever to write them that way: They are listed in priority order. Since IRQ 2 chains to 9 (really 8, but 8 isn't typically available for user assignment), those have the same priority as 2. After all of those, his list continues with 3, 4, etc.

Interrupts of a higher priority can barge in on interrupts of a lower priority. This means, if you set your sound card to IRQ 7, which is last, every single other interrupt in the machine can interrupt the sound card interrupt handler in the middle of whatever it's doing. Unfortunately, my 8088flex system has the opposite problem: I typically have mine on 2 on my XT system, and my hard drive is fixed on 5, so the sound card interrupts the hard disk in the middle of reading data. For small transfers, this is ok; for larger transfers (which would really speed things up), it takes too long and the hard drive controller routine in the BIOS locks up.

All this has given me a perspective of how hard things were in the early days ;-)
 
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