VOGONS


First post, by McBierle

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"Quick" question:
I recently got a CM-64 without cables. I made a cable via this http://amorphe-welt.de/bastelei/midi/midikabel.html

DIN - D-sub
---------------
2 - 4
4 - 8
5 - 15

After a quick test i diddn't get sound, so i want to know if this pinout is correct, so i can rule the cable out.

Thanks

Reply 1 of 12, by keropi

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this is a simple schematic for a gameport->midi-out adapter:

tzvAwcJl.png

you connect it to the CM-64's IN port and it will work fine... straight cable connections are not a good idea.

🎵Link to buy a PCMIDI mpu
🎧Orpheus soundcard project
💻WTB Amstrad PC7486SLC-33 system

Reply 2 of 12, by McBierle

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Ok thanks, if i get a 74LS00 i'll do that thing.
But, should i have gotten sound or not? What will/would happen with a straight connection?

What about those midi/gameport-cables you can get on amazon/ebay? Do the have this circuit?

Reply 3 of 12, by gdjacobs

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Quite a few ways it can go wrong when directly connected. Part of the reason for the physical connection spec is that it's much more predictable.

All hail the Great Capacitor Brand Finder

Reply 4 of 12, by Tiido

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With direct connection there may not be enough current to drive the LED in the optoisolator on the receiving end, depending on what sort of resistor is used in series with the MIDI line.

T-04YBSC, a new YMF71x based sound card & Official VOGONS thread about it
Newly made 4MB 60ns 30pin SIMMs ~
mida sa loed ? nagunii aru ei saa 😜

Reply 5 of 12, by McBierle

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keropi wrote:
this is a simple schematic for a gameport->midi-out adapter: […]
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this is a simple schematic for a gameport->midi-out adapter:

tzvAwcJl.png

you connect it to the CM-64's IN port and it will work fine... straight cable connections are not a good idea.

Ok got a 74LS00. Ist pin 15 not connected? or ist there a line missing in that graphic`? And 8 and 9 are not connected?

Reply 7 of 12, by keropi

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yes the schematic is edited to only include the MIDI out port , the IN port requires some more components and it is not needed for gaming/playback

🎵Link to buy a PCMIDI mpu
🎧Orpheus soundcard project
💻WTB Amstrad PC7486SLC-33 system

Reply 8 of 12, by gdjacobs

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By convention NAND gate pins 1, 2, 4, and 5 should be strapped to ground (or +5V) and not allowed to float.

All hail the Great Capacitor Brand Finder

Reply 11 of 12, by McBierle

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Yes exactly, but in that pic/schematic the din-connector is "midi out".

edit: i know, i'm counting beans here. I know that the midi signals are going out on that side. But if you have a connector on a device that is called "midi out" i would use another description 😁

Reply 12 of 12, by McBierle

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Oh i forgot, many thanks it works!

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