VOGONS


MIDILPT

Topic actions

First post, by dreamblaster

User metadata
Rank Oldbie
Rank
Oldbie

hi,

I started work on a new project : MIDILPT :

MIDI interface on parallel port.
The idea is to make it work with SOFTMPU.
I tried to design it with through hole components only,
so it could become an easy solder kit.
The result is pretty large : approx 55mm x 55mm

Would this make sense ?

Attachments

  • midilpt_top3d.png
    Filename
    midilpt_top3d.png
    File size
    41.14 KiB
    Views
    2433 views
    File license
    Fair use/fair dealing exception
  • midilpt_front.png
    Filename
    midilpt_front.png
    File size
    81.59 KiB
    Views
    2433 views
    File license
    Fair use/fair dealing exception
  • midilpt_back.png
    Filename
    midilpt_back.png
    File size
    71.27 KiB
    Views
    2433 views
    File license
    Fair use/fair dealing exception
  • midilpt_3d_view.png
    Filename
    midilpt_3d_view.png
    File size
    36.12 KiB
    Views
    2433 views
    File license
    Fair use/fair dealing exception

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 1 of 26, by keropi

User metadata
Rank l33t++
Rank
l33t++

very nice!!!!
I can see it working on some retro-gaming laptops - now to create a *LPT base to have all the devices connected 😊

🎵 🎧 PCMIDI MPU , OrpheusII , Action Rewind , Megacard and 🎶GoldLib soundcard website

Reply 2 of 26, by M-HT

User metadata
Rank Newbie
Rank
Newbie

Would it make sense to have place on the PCB for Waveblaster header ? To either use MIDI out or Waveblaster header in case you already have DreamBlaster S1,X1, S2 or X2.

Reply 3 of 26, by Scali

User metadata
Rank l33t
Rank
l33t

So, the device would basically have a parallel-to-serial interface? Basically just a UART? And SoftMPU will provide full MPU-401 compatibility? At least for midi-out.

http://scalibq.wordpress.com/just-keeping-it- … ro-programming/

Reply 4 of 26, by dreamblaster

User metadata
Rank Oldbie
Rank
Oldbie
Scali wrote:

So, the device would basically have a parallel-to-serial interface? Basically just a UART? And SoftMPU will provide full MPU-401 compatibility? At least for midi-out.

yes, that's the idea

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 6 of 26, by dreamblaster

User metadata
Rank Oldbie
Rank
Oldbie

redesign, using attiny to make smaller pcb, better ergonomics,
dual 3.5mm MIDI OUT (it will use 3.5mm to DIN cables), reset button..

midilpt.png
Filename
midilpt.png
File size
31.8 KiB
Views
2248 views
File license
Fair use/fair dealing exception

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 7 of 26, by xjas

User metadata
Rank l33t
Rank
l33t

Looking good! Are those dual individual MIDI buses (i.e. 16 channels EACH) or do they just mirror each other? Being able to drive two independent multitimbral devices (i.e. a JV1010 and Yamaha XG module in my case) would be super useful.

MIDI IN would also be nice, even if it's just a pinheader on the PCB.

SoftMPU should cover DOS support well, but I'm thinking I might take a stab at writing a VXD driver for this thing (how hard could it be??) when it's further along in development. Any interest in that?

Last edited by xjas on 2018-05-13, 20:44. Edited 1 time in total.

twitch.tv/oldskooljay - playing the obscure, forgotten & weird - most Tuesdays & Thursdays @ 6:30 PM PDT. Bonus streams elsewhen!

Reply 8 of 26, by Scali

User metadata
Rank l33t
Rank
l33t

Looks very nice!
I think it may especially be useful for old 386+ laptops that you can't add midi to in any other way.
It's probably also going to be cheaper than an ISA card.

http://scalibq.wordpress.com/just-keeping-it- … ro-programming/

Reply 9 of 26, by dreamblaster

User metadata
Rank Oldbie
Rank
Oldbie
xjas wrote:

Looking good! Are those dual individual MIDI buses (i.e. 16 channels EACH) or do they just mirror each other?

It is just mirrored, both outputs have exactly the same signal

xjas wrote:

MIDI IN would also be nice, even if it's just a pinheader on the PCB.

hmm right now, only midi out

xjas wrote:

SoftMPU should cover DOS support well, but I'm thinking I might take a stab at writing a VXD driver for this thing (how hard could it be??) when it's further along in development. Any interest in that?

That would be GREAT !

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 10 of 26, by dreamblaster

User metadata
Rank Oldbie
Rank
Oldbie

How about this feature ?
now that there's a CPU, considering to send 'all notes off' on bootup
--> this will allow to shutdown midi hanging notes by pressing reset.

Also will try to keep the interfacing compatible with S2P
--> same pinout, same drivers 😀

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 11 of 26, by xjas

User metadata
Rank l33t
Rank
l33t

The mirrored ports are still handy as it cuts down on the number of pass-throughs needed. If you could find a way to cram on a MIDI-IN, I can think of a bunch of applications it would be great for - using a '90s laptop as an OPL3 sound module for example, or sending a MIDI clock between two machines for sync.

dreamblaster wrote:

How about this feature ?
now that there's a CPU, considering to send 'all notes off' on bootup
--> this will allow to shutdown midi hanging notes by pressing reset.

Yeah a kill switch is always handy, I haven't run into a hung note in my own setup in a while but it's nice to have a clean way to zap them.

dreamblaster wrote:

Also will try to keep the interfacing compatible with S2P
--> same pinout, same drivers 😀

That would be sweet, that means I could essentially start with a Win9x port of the version of SoftMPU for S2P & support both devices. I found a VxD guide with some sample code online and it doesn't seem too complicated. I'm relatively new to Win9x coding though; will be a great way to expand my range. 😀

twitch.tv/oldskooljay - playing the obscure, forgotten & weird - most Tuesdays & Thursdays @ 6:30 PM PDT. Bonus streams elsewhen!

Reply 12 of 26, by dreamblaster

User metadata
Rank Oldbie
Rank
Oldbie
xjas wrote:

That would be sweet, that means I could essentially start with a Win9x port of the version of SoftMPU for S2P & support both devices. I found a VxD guide with some sample code online and it doesn't seem too complicated. I'm relatively new to Win9x coding though; will be a great way to expand my range. 😀

Yes ! I will PM you

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 13 of 26, by dreamblaster

User metadata
Rank Oldbie
Rank
Oldbie

MIDILPT PCB's ordered
to be continued when they arrive

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 14 of 26, by matze79

User metadata
Rank l33t
Rank
l33t

Why do 2 modules ? 😀 just add a wavetable header

https://www.retrokits.de - blog, retro projects, hdd clicker, diy soundcards etc
https://www.retroianer.de - german retro computer board

Reply 15 of 26, by Super_Relay

User metadata
Rank Newbie
Rank
Newbie
matze79 wrote:

Why do 2 modules ? 😀 just add a wavetable header

the biggest problem you have with a wavetable header is that while the s2/x2 work on purely 5 volts most other wavetable cards require +12v and -12v which you can't source nearly so easily.

I made a daughter board to use the s1 with dosbox on a raspberry pi and if i wanted it to be able to use a yamaha DB50XG or even a smaller diamond wavetable card i would basically need to put an ATX power connector on it to get the voltages required to run them.

Reply 16 of 26, by dreamblaster

User metadata
Rank Oldbie
Rank
Oldbie

The PCB is ready and soldered ...

MIDILPT.jpg
Filename
MIDILPT.jpg
File size
128.19 KiB
Views
1956 views
File license
Fair use/fair dealing exception

(no coding yet)

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 17 of 26, by matze79

User metadata
Rank l33t
Rank
l33t

No Firmware ? 😀

https://www.retrokits.de - blog, retro projects, hdd clicker, diy soundcards etc
https://www.retroianer.de - german retro computer board

Reply 18 of 26, by dreamblaster

User metadata
Rank Oldbie
Rank
Oldbie
matze79 wrote:

No Firmware ? 😀

not yet

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !