[linux-audio-user] Connecting to external midi device

[Clemens Ladisch]

Adrian Blockley wrote:
> I am trying to connect to an external midi device  (casio CTK-900
> keyboard) through  a cheap soundcard  (Cmedia 3738 chip) with
> midi interface.
> 
> Running 
> aplaymidi --port 16:0 mysong.MID 
> 
> produces no output or error message but the following is printed using
> dmesg:
> 
> cmd: 0xff failed at 0x330 (status = 0xff, data = 0xff)

This means the MIDI port wasn't initialized correctly.

It seems C-Media changed their latest chip revisions in some
incompatible way.

> My guess is that the midi i/o port address is wrong. Now i don't
> understand a great deal about PCI but my guess is that the midi i/o port
> address on the sound card probably isn't 0x330 (please note I've also
> tried 300, 310 and 320).

The driver configures the card to use the port address that was
specified by the user.  Well, it tries to.

> I've tried using the Windows device manager to find out what address
> port I should be using but i can only find the address of the sound
> card and not the mpu401.

The card shadows the MIDI port registers in its main PCI address space,
but the instructions in C-Media's so-called datasheet don't work.

I'd recommend to get another card.  Any other card.


HTH
Clemens