Problem with ASUS onboard MIDI

Miscellaneous
1

After the recommendations here, I’m trying to switch my MIDI over to my motherboard’s built-in MPU401 circuit.

I’m running an ASUS A7N8X-E, which uses an optional PCI panel for a 15 pin Joystick/MIDI port, two additional USB ports and sometimes an extra COM port. I had a Sub 15 on a panel anyway, so I decided to wire it to a ribbon, but I’m not getting anything in either direction. I was wondering how most of you guys would go about troubleshooting such a problem.

Details-

I’m using a homemade 15 pin to MIDI adapter, which I built years ago from a web schematic. I think it includes a 4N35 optocoupler and a hex buffer along with a couple caps and resistors. I’ve gone back and checked it again on another machine to make sure it still works.

Going by the ASUS manual, there are a total of 3- 5v pins on the MB header and two ground pins. All 5v pins they list are tied together, as are the two ground pins, so I don’t guess it matters which ones I use for supply. I read 4.8 something volts at my 15pin, so I guess my supply and wiring are OK. The other two connections have been double checked at both ends, so their wiring is OK as well

I’ve tried a wide variety of NForce chipset software, I’ve switched the BIOS settings from the default 10/330, I’ve used a few different MIDI apps, and I’ve most recently done a clean Win2Ksp4 install, replacing my XPPro OS (not just for the MIDI problem). I also tried reversing the MIDI in and out pins in case they made a typo. Both versions of Windows detected and installed an MPU-401 driver, so I guess it’s turned on properly.

I’m thinking tonight I may put a full ribbon on the header and try some of the other (joystick) pins to see if they are carrying the MIDI, but I doubt it. Out of curiosity, I checked the voltage at the two MIDI pins and had the full 4.8v supply at one and something in the high 3v range at the other, but I don’t know what to expect from a constantly changing signal or what it should read in it’s idle state. There’s a scope out there, but I really only use it for setting tape heads.

Can anyone think of anything else to check?

                                     -Thanks

George

PS- I’d throw in a cheap SB clone, but I’m clogged up with PCI junk, including two UAD cards that keep my case nice and hot  :frowning:

2

Who recommended Joystick midi? What’s the alternative?

I’d try a commercial joystick-midi convertor. You can always say “If it doesn’t work, can I bring it back for a refund?”.

This will tell us if it’s the cable or not. Us techo’s call it using “known-good” parts

Good luck, Let me know how you go

3

Stryd_one,

I’ve got a thread a couple notches down asking about the different types of MIDI interfaces. Nobody actually recommended the game port thing, it was more a recommendation *against* USB, and I’ve been having a crap time with the particular USB interface I use, having it disappear on me, etc.

As for the ASUS circuit, it was a “good” night (just too long). I got MIDI happening. Their pinouts evidently were correct, but I was only able to get it working after running almost a straight path between the MB header and the devices. I think I had a couple 270ohm resistors in there for flavor, but that was it. It doesn’t seem to agree with the 15 pin to MIDI circuit I had been using (which works great with many other cheap soundcards). Nothing seems to make it through the optocouple or the inverter/buffer chip. No IN or OUT. I even tried an external power supply for the adapter to make sure their 5v power was OK.

I don’t get it. I thought those buffered adapters were the correct way to interface MIDI, and remember reading that some of the cheap adapter cables just ran straight through instead. If anyone knows the safest form of “passive” 15 pin to MIDI adapter, I’ll be looking over the next day or so.

I’m also constantly looking for an up to date DIY solution (other than game port).

BTW - I think this link is the same 4N35/7407 circuit I use (it may have a minor pinout error from what I remember, but mine was corrected)

http://www.harmony-central.com/MIDI/sbmidi.zip

                          -Take Care

George

PS- The machine sent a stream of SysEx and received a bunch of note messages to test the i/o. Other than that, I won’t know how well it does for a few days. 

4

Heh, that most recent thread dissing USB MIDI… That was me :slight_smile:

USB MIDI sucks, but so does onboard!

As for DIY MIDI  interfaces, I wouldn’t bother. You can get Parallel or Serial 8 port MIDI interfaces for SO cheap on ebay now man.

Check these :

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&category=23792&item=7310724927&rd=1      works with serial, 70 UK Pounds

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&category=23317&item=7310883007&rd=1      ditto

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&category=41784&item=7310070757&rd=1      same, 200US, thats too much

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&category=23317&item=7309075375&rd=1      same, 45 euro

You get the idea… :slight_smile:

5

Heh, that most recent thread dissing USB MIDI… That was me :slight_smile:

Indeed it was!  - Thanks again

I hadn’t noticed the Emagics. I’ve checked periodically for the older MTPAV’s. It’s hard to find any users in the Steinberg forums recommending any of them though. I don’t even think they like the Midex there. I think there are a couple with old MTPAV’s, but I’ve also read of a couple problems with them. I had one on a PC at a studio I was working at and I remember it being sort of flakey as well.

Like I mentioned in the other post, my MIDI setup is fairly “modest”. I also have *two* 8x8 patchbays here, so a 1x1 or 2x2 connection to the computer can suffice most of the time. I may try the soundcard MIDI for a little while and see if it gets me by and then just keep an eye out for something better.

I wish old parallel boxes could work with some standard current driver for XP/2K. I’ve got a MIDIPort parallel here and there’s an Atmel based circuit by the MaxMIDI guy, but it’s from way back in the 3.1/Win95 days.  (I take that back— the MaxMIDI is actually serial  - just checked)

                            -Take Care

George