VOGONS


First post, by Tronix

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Hello,

Recently, I made an expansion card based on CPLD Altera epm3256. The main purpose of this card is the logical analyzer of the ISA bus signals. In addition, the card has an SD and minijack 3.5 connector.

9ca36bff451203451d53d9fe6edced61-full.jpg

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I did implement ports 0x378 and 0x278 for the emulation of two Covox's at LPT1 and LPT2. So, minijack left channel - covox at LPT1 and right channel - covox at LPT2. This is a stereo using two covox's.

I'm trying to use FastTracker II for playing modules. Separatly, there are no problems. I can easily switch from LPT1 to LPT2 and I hear music in the right (when i chose LPT1) or left (when i chose LPT2) channels. Worked wery well. Real record from LPT1 in mono mode here: https://clyp.it/fjeyp5kr

BUT when i chose LPT1+LPT2 and check checkbox "Stereo" - FastTracker halted. Sometimes, unexpected exit to DOS with debug information about registers and stack.

vzxmhgjwf_b7v7qizrkorpo1j3g.png

What am I doing wrong?

Last edited by Tronix on 2018-10-19, 12:33. Edited 1 time in total.

Reply 1 of 9, by jxalex

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how it behaves if you have not ticked that "Stereo", but have the LPT1+LPT2 ?
The FT2 has also stereo playing capability with LPT1 only too.

if this does not help then...

1. is it under plain DOS?
2. have you tried with different FT2 versions too (2.06, 2.08 or 209) are very different from each other with its behaviour.
3. expansion cards which use the same IRQs or ports?

Current project: DOS ISA soundcard with 24bit/96Khz digital I/O, SB16 compatible switchable.
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Reply 2 of 9, by Tronix

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jxalex wrote:

how it behaves if you have not ticked that "Stereo", but have the LPT1+LPT2 ?

It does not hang, but playing using only LPT1 port (0x378). I see with the help of some Verilog watchpoint that there are no calls to port 0x278 in this mode.

jxalex wrote:

The FT2 has also stereo playing capability with LPT1 only too.

I know, but when multiplexing channels with LPT1 only the frequency of samplerate should fall. Is not it?

jxalex wrote:
if this does not help then... […]
Show full quote

if this does not help then...

1. is it under plain DOS?
2. have you tried with different FT2 versions too (2.06, 2.08 or 209) are very different from each other with its behaviour.
3. expansion cards which use the same IRQs or ports?

1) Yep, i running FT2 under plain DOS.
2) Yes, i am trying different FT2 versions - 2.06, 2.09.
3) I don't use IRQ at my card and disable onboard LPT1 port in BIOS CMOS setup. My config: 430TX motherboard with iP166 MMX, 128Mb RAM.

Reply 3 of 9, by jxalex

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At first I thought that perhaps if the BIOS do not recognize the LPT2 then it has some trouble but then it is not the case if it was running already with that.

How it behaves on other machine which has the 2 LPT ports? Also if the machine has its LPT port adress something other?

Sometimes there are very strange or ridiculous reasons at first point which does not make sense at first.
strange thought, but several things can be tried:

*trying with lower memory amount? (16MB for example when thinking about 8237 controller).
* Clocking down the memory timings and bus speeds.
* Swapping the videocard for some other type?

And just one change in time.

Also: does it run with other music software which can use 2 LPT ports? MODPLAY 2.19, Megaplay, and other covox based players?

Current project: DOS ISA soundcard with 24bit/96Khz digital I/O, SB16 compatible switchable.
newly made SB-clone ...with 24bit and AES/EBU... join in development!

Reply 4 of 9, by Tronix

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jxalex wrote:

How it behaves on other machine which has the 2 LPT ports? Also if the machine has its LPT port adress something other?

I have no other real machines with two LPT. I compiled 86-box emulator (PCem fork) from sources - It supports 2 LPT ports and can emulate COVOX on each of them. It can also emulate 430HX/VX chipset and Pentium class processor, so, emulation is very similar to my real configuration. I chose ASUS P/I-P55T2P4 motherboard, Pentium 166 CPU and S3 Trio 64 videocard. Booted up and.... The behavior of the FT2 is 100% repeatable behavior on a real machine - sometimes hung up, sometimes crashes with registers dump.

I repeat, separatly I can freely switch between LPT1 or LPT2 output - it's okay. If machine or emulator has the same port address with something other i think i don't listening music when switch to LPT2 from LPT1.

jxalex wrote:
Sometimes there are very strange or ridiculous reasons at first point which does not make sense at first. strange thought, but s […]
Show full quote

Sometimes there are very strange or ridiculous reasons at first point which does not make sense at first.
strange thought, but several things can be tried:

*trying with lower memory amount? (16MB for example when thinking about 8237 controller).
* Clocking down the memory timings and bus speeds.
* Swapping the videocard for some other type?

And just one change in time.

In 86-box emulator i can do it simple, but this 'magic' doesn't work here. I'm pretty sure that this is a software bug in the FastTracker 2. Perhaps due to the fact that no one really used this feature or tested it.

jxalex wrote:

Also: does it run with other music software which can use 2 LPT ports? MODPLAY 2.19, Megaplay, and other covox based players?

I'll try later.

Reply 5 of 9, by jxalex

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Yes, it really seems the software bug, but just try with the MODPLAY (the SOUNDCLUB is the another one which uses 2 LPT ports) and Megaplay.

I can put together a machine with 2 LPT ports and try this myself here too later.
So far I did not used this 2 port feature becouse before I got the 2 LPT cards, I already got the Gravis. And during 2 LPT port on those ancient times I saw 2 machines run only Megaplay and Soundclub.

by the way, out of curiosity... Why?
trying with COVOXes just for fun? Are You doing such debug-tracing with FT2 "becouse it is there"?

Current project: DOS ISA soundcard with 24bit/96Khz digital I/O, SB16 compatible switchable.
newly made SB-clone ...with 24bit and AES/EBU... join in development!

Reply 6 of 9, by shock__

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Tronix wrote:

I know, but when multiplexing channels with LPT1 only the frequency of samplerate should fall. Is not it?

That is correct. There are also implementations which go from 8 bit to 4 bit per channel while keeping the samplerate, but those are quite uncommon.

Current Project: new GUS PnP compatible soundcard

[Z?]

Reply 8 of 9, by Fagear

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Sorry for necroposting.

Tronix wrote on 2018-10-19, 07:47:

BUT when i chose LPT1+LPT2 and check checkbox "Stereo" - FastTracker halted. Sometimes, unexpected exit to DOS with debug information about registers and stack.

I have the same problem. LPT1+LPT2 simply does not work in FT2.

DevanWolf wrote on 2019-08-26, 18:09:

Have you tried this later version of FT2?

Does not work as well.

I've tried on 386SX-40, 386DX-40 and X5-120 (486) systems with the same results: https://www.youtube.com/watch?v=pAozmlN6o08

New BIG soundcard: FMonster.
Covox Sound Master replica
Innovation SSI-2001 replica & DuoSID.
My audio/video collection.

Reply 9 of 9, by matze79

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Also does not work for me, using a real LPT and a DAC on ISA Bus registred as LPT2.

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