BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Discussion about old sound cards, MIDI devices and sound related accessories.

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby canthearu » 2019-7-21 @ 12:04

Couple of photos

Front of card:
IMG_0288.JPG


Back of card:
IMG_0289.JPG


Not the best soldering, scratched some of the green coating in a few places, but still works great. Was a little tricky due to tight spacing, and was a surprisingly large number of components.
canthearu
Oldbie
 
Posts: 647
Joined: 2018-5-26 @ 01:00

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby LABS » 2019-7-21 @ 22:45

As long as some of you have already assembled the card and tried it on your systems - can anyone give any feedback with issues/suggestions I need to pay attention to?

root42 spotted some clicks in DoTT on his 386/25 machine. It turned out that his ISA bus was running on 6MHz, after changing it to a standard 8Mhz the clicks were gone, but anyway ISA speed can be as low as 4MHz on some systems and I should consider it.

I'm preparing a firmware upgrade and PCBs for the next batch, so any feedback is important.

PS: Thanks to your support I finally ordered a Siglent SDS1202X-E oscilloscope and LA5016 logic analyzer :cool:
User avatar
LABS
Member
 
Posts: 128
Joined: 2018-6-07 @ 16:49
Location: Riga, LV

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby Tiido » 2019-7-22 @ 05:14

Congrats, that scope looks fancy ~
User avatar
Tiido
Oldbie
 
Posts: 933
Joined: 2018-1-14 @ 04:40
Location: Estonia

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby canthearu » 2019-7-22 @ 13:43

LABS - you totally deserve the logic analyzer and oscilloscope.

The analog part of the blasterboard is simply outstanding. I plug in my reasonably good headphones, turn the volume up, and I hear nothing. Can't find the noise floor of this card. And it provides perfectly reasonable amplification quality as well for an amp that isn't particularly designed around amplifying for headphones.

The changes to the blasterboard I would suggest are pretty minor:

a) A normal CDROM 4 pin header would work better then the 3 pin the blasterboard has. I also found the amplification of the cdrom input to be not as strong as the other inputs.
b) A way of upgrading the ATmega's firmware without pulling it out of the socket and plugging into my eeprom programmer (can the ATmega reprogram itself using DMA transfers?)
c) Can we emulate the C/MS chips inside the ATmega as well?

In any case, I'm happy to beta test any firmware updates you wish to share. I have a number of systems I can test it on.
canthearu
Oldbie
 
Posts: 647
Joined: 2018-5-26 @ 01:00

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby LABS » 2019-7-22 @ 15:04

Thanks, canthearu. I'm glad that you could appreciate the main bb's feature.

a) Different CD-ROM manufacturers (Sony/Mitsumi/Panasonic) has different analog out pinouts. The idea was - with my cable you can rearrange the pins as your CD-ROM requires and connect it to this single 3-pin header on the board. Otherwise there should be at least three 4-pin headers only for CD, but there is no space for that:) The included cable works fine, despite it is not shielded.
CD amplification depends on your CD-ROM's output level. The amp was designed with a reference input of the most quiet of 3 CD-ROMs I have. I met some models whose rear analog output was dependent on the front volume regulator as well.
You also can add the CD gain by changing R32 and R33 from default 33k to 27k or 22k. I do not recommend going lower than 15k.

b) An ability to program ATmega onboard is fancy, but it requires significant changes and complication of the schematics - adding secondary MCU which will communicate with ISA bus and program the main MCU + some pin multiplexing logic. I will implement this ability in my next project which is now in a prototype development stage and is too early to talk about ;)

c) I should check this out.
User avatar
LABS
Member
 
Posts: 128
Joined: 2018-6-07 @ 16:49
Location: Riga, LV

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby LABS » 2019-7-22 @ 15:15

Good news, JLCPCB finally added a dedicated option for their ID placement we talked about.

jlcid.jpg
User avatar
LABS
Member
 
Posts: 128
Joined: 2018-6-07 @ 16:49
Location: Riga, LV

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby mothergoose729 » 2019-7-22 @ 15:21

Great project! I have been looking at SB Pro 2.0 boards lately. So very expensive.

Are you selling these as kits? Do you have a storefront? Thanks :)
mothergoose729
Member
 
Posts: 400
Joined: 2018-4-10 @ 03:04

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby LABS » 2019-7-22 @ 15:54

mothergoose729 wrote:Great project! I have been looking at SB Pro 2.0 boards lately. So very expensive.

Are you selling these as kits? Do you have a storefront? Thanks :)


The kit is for a SB 2.0-compatible card, not SB Pro 2.0. Check PM.
User avatar
LABS
Member
 
Posts: 128
Joined: 2018-6-07 @ 16:49
Location: Riga, LV

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby MJay99 » 2019-7-22 @ 20:34

LABS wrote:As long as some of you have already assembled the card and tried it on your systems - can anyone give any feedback with issues/suggestions I need to pay attention to?


Nothing to really mention, yet. Maybe in terms of usabilty, I might expect the volume knobs in an inverted order (or the output-connector on top of all the current knobs, instead of below), as that would more reflect my mental picture of priority (output near SB knob, then OPL, PC-Spk, CD) - but that's surely much too much change to even consider for nothing of a functional gain.

Then, just for trying something extreme, today, I put it into a P4 system with FreeDOS 1.2 and then tried DOTT on it (since it seemed a little fragile in the other tests before): resulted in the SB becoming an alarm siren each time :happy: The AWE32 I replaced it with was able to produce music, but DOTT also ended up crashing soon after. So far, I'm thinking it's more the out-of-era system and OS than anything else - so I'll keep meddling with it the upcoming days and and am gonna report back, if anything comes up.

LABS wrote:PS: Thanks to your support I finally ordered a Siglent SDS1202X-E oscilloscope and LA5016 logic analyzer :cool:


Oh, great, that's very well deserved! The Blasterboard's absence of any noticable noise is still impressing me each time.
MJay99
Newbie
 
Posts: 27
Joined: 2018-9-13 @ 14:22
Location: Bavaria, Germany

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby keropi » 2019-7-22 @ 20:48

I have tried a real SB2.0 CT1350B with a couple of pentium1 200mmx systems and I found it did not work well. On the same systems a SB PRO2 CT1600 is fine.
This is not unexpected, the SB2.0 was not meant to be used with such speedy systems, I would say a 486DX2/66 is the top ceiling for such old SB cards...

Having said that BlasterBoard is newer and could have more tolerance but it's still based on the SB2.0 so let's not overshoot LOL
User avatar
keropi
l33t++
 
Posts: 7124
Joined: 2003-9-08 @ 06:45
Location: Greece

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby 640K!enough » 2019-7-22 @ 21:07

LABS wrote:An ability to program ATmega onboard is fancy, but it requires significant changes and complication of the schematics - adding secondary MCU which will communicate with ISA bus and program the main MCU + some pin multiplexing logic.

Unless there is a specific reason for that choice, I don't think it absolutely requires a second MCU. With some additional logic, you should be able to implement a simple bootloader that would program the appropriate portion of the flash when given the appropriate commands. Upon boot, without the programming functionality being triggered, the bootloader would just pass control to the code stored in the aforementioned flash region. This would be similar to the way the original Arduino boards implemented the USB bootloader on AVR.

Depending on how well that fits with your other design goals, that may be something to consider. It involves an initial investment in developing the software, but might help reduce the BOM costs long-term.
640K!enough
Member
 
Posts: 491
Joined: 2017-5-11 @ 17:52
Location: Canada

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby Fagear » 2019-7-22 @ 21:10

I've got my kit on 9th July, but had no time to play with it since. :depressed:
Just unraveled the box.

2019-07-22 23.54.49.jpg
Parcel from LABS
2019-07-22 23.55.22.jpg
BLASTERBOARD kit in a box
User avatar
Fagear
Member
 
Posts: 255
Joined: 2014-7-10 @ 22:27
Location: Russia, Moscow

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby FreddyV » 2019-7-22 @ 21:13

Hi,

I already added my idea :) Add a DMA Mode in Signed mode (To not have to do the XOR 80h before sending a signed buffer)

I suppose that you decode the @ in hardware, because It may be simple to emulate the Tandy 1000 sound, and covox if you can add more I/O decoding.

FreddyV
FreddyV
Newbie
 
Posts: 65
Joined: 2019-4-08 @ 11:58

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby canthearu » 2019-7-23 @ 02:03

keropi wrote:Having said that BlasterBoard is newer and could have more tolerance but it's still based on the SB2.0 so let's not overshoot LOL


I'll chuck the blasterboard into a P3-600 (my fastest ISA system and see how it handles it.
canthearu
Oldbie
 
Posts: 647
Joined: 2018-5-26 @ 01:00

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby canthearu » 2019-7-23 @ 02:12

LABS wrote:Thanks, canthearu. I'm glad that you could appreciate the main bb's feature.

a) Different CD-ROM manufacturers (Sony/Mitsumi/Panasonic) has different analog out pinouts. The idea was - with my cable you can rearrange the pins as your CD-ROM requires and connect it to this single 3-pin header on the board. Otherwise there should be at least three 4-pin headers only for CD, but there is no space for that:) The included cable works fine, despite it is not shielded.

I would say stick to the most standard (Right - Ground - Ground - Left) that would work with the vast majority of IDE drives. But of course, this is not major, mearly me nitpicking.

LABS wrote:CD amplification depends on your CD-ROM's output level. The amp was designed with a reference input of the most quiet of 3 CD-ROMs I have. I met some models whose rear analog output was dependent on the front volume regulator as well.
You also can add the CD gain by changing R32 and R33 from default 33k to 27k or 22k. I do not recommend going lower than 15k.

Thanks for the tip. For this particular drive, the gain is not too low, but I have to crank it much further up than the WAVE/OPL2 channels. Again, me totally nitpicking :)

LABS wrote:b) An ability to program ATmega onboard is fancy, but it requires significant changes and complication of the schematics - adding secondary MCU which will communicate with ISA bus and program the main MCU + some pin multiplexing logic. I will implement this ability in my next project which is now in a prototype development stage and is too early to talk about ;)


Yeah, if it requires a redesign of the board to add extra ICs and such, then not worth it. If it can be reprogrammed over the ISA bus with either all software, or only minor hardware changes, then I think you should pursue it.
LABS wrote:c) I should check this out.


Would really depend if the C/MS is controlled on the same I/O ports as the WAVE/OPL2 chip, and how much horsepower you need in the ATmega to create a passable copy of the C/MS sound chips. Of course, it could never be stereo like I think the original C/MS was, but I doubt any software really took advantage of it.
canthearu
Oldbie
 
Posts: 647
Joined: 2018-5-26 @ 01:00

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby ajacocks » 2019-7-23 @ 13:14

This looks like a fantastic project, and I’d love to build one, myself. Are there any more kits available?

Thanks!
- Alex
ajacocks
Newbie
 
Posts: 10
Joined: 2017-7-10 @ 15:33

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby root42 » 2019-7-23 @ 13:29

canthearu wrote:
LABS wrote:c) I should check this out.


Would really depend if the C/MS is controlled on the same I/O ports as the WAVE/OPL2 chip, and how much horsepower you need in the ATmega to create a passable copy of the C/MS sound chips. Of course, it could never be stereo like I think the original C/MS was, but I doubt any software really took advantage of it.


I beg to differ! All the games I have tested so far with the MUS1099 used stereo. I mean, you probably don't NEED stereo, but it's the distinguishing feature of the C/MS. At the moment I have the MUS1099 plugged in at 210h and the Blasterboard at 220. But having only one card, especially with a good noise level would be awesome.
Soldering, retro game reviews and more on YouTube and Bonus videos
80386DX@25 MHz, 8 MiB RAM, Tseng ET4000 1 MiB, Jazz16, PC MIDI Card + SC55MkII + MT32, XT CF Lite, OSSC 1.6
User avatar
root42
Oldbie
 
Posts: 1159
Joined: 2018-1-27 @ 13:23

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby canthearu » 2019-7-23 @ 14:53

Testing in the Pentium III 600, the DAC output doesn't sound quite right in windows.

I'm going to do some more tests I guess to see if it only some bitrates as games in DOS don't seem too bad.

Edit: OK, sound is definitely much rougher on the P3-600, when comparing a song I converted to 44100hz Mono 8-bit PCM on both my main computer and the P3-600 using blasterboard.

Edit 2: I'll test it on the 486 again tomorrow and see if I can reproduce the same roughness with PCM playback in windows on it.
canthearu
Oldbie
 
Posts: 647
Joined: 2018-5-26 @ 01:00

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby LABS » 2019-7-23 @ 21:03

canthearu wrote:Testing in the Pentium III 600, the DAC output doesn't sound quite right in windows.

I'm going to do some more tests I guess to see if it only some bitrates as games in DOS don't seem too bad.

Edit: OK, sound is definitely much rougher on the P3-600, when comparing a song I converted to 44100hz Mono 8-bit PCM on both my main computer and the P3-600 using blasterboard.

Edit 2: I'll test it on the 486 again tomorrow and see if I can reproduce the same roughness with PCM playback in windows on it.


Noisy playback in Windows (I assume you are running W95/98) does not depend on cpu speed. You don't hear a bit-to-bit accurate playback because Windows apply internal mixing and sample conversion in real time and the result sounds like crap. You should try DirectSound games like Diablo, Starcraft, Hexen II and hear how they sound, outputting directly:)
High CPU speed does not degrade the output under DOS, as ISA bus speed remains the same. Some games just may not have sound at all on faster machines, like early SCUMM-based games, which use finite loops when waiting for DSP response and just give up too early. The same is with OPL2 - the sirens you talked about earlier. Anyway, it is a user's responsibility which software to run on which hardware.
Last edited by LABS on 2019-7-23 @ 22:33, edited 1 time in total.
User avatar
LABS
Member
 
Posts: 128
Joined: 2018-6-07 @ 16:49
Location: Riga, LV

Re: BLASTERBOARD : A new SB 2.0-compatible ISA sound card

Postby LABS » 2019-7-23 @ 21:13

Nevertheless, I just disassembled and decoded to a human-readable form the original firmware of Sound Blaster 2.0 (DSP 2.01). Many unknown things revealed and there is a room for perfection for BB's future firmware releases.
Last edited by LABS on 2019-7-23 @ 22:33, edited 1 time in total.
User avatar
LABS
Member
 
Posts: 128
Joined: 2018-6-07 @ 16:49
Location: Riga, LV

PreviousNext

Return to Sound

Who is online

Users browsing this forum: Google [Bot], MMaximus and 3 guests