How to use AN00125 USB Mass Storage Class with xCORE-200 Mul

[gearthwormist]

Trying to get the USB Mass Storage Class example from AN00125 to work on an xCORE-200 Multichannel Audio Platform board. After modifying the code to work with that board, when I run the project, the board does not appear on the USB bus.

Using the debugger, I have determined that tile[1] core[2] is stuck in XUD_Manager_loop waiting for the USB clock:

Code: Select all

        /* Wait for USB clock (typically 1ms after reset) */        p_usb_clk when pinseq(1) :> int _;

I have attached an archive of the project I am working on. (For some reason the xk-audio-216-mc.xn file was not included in the archive; I am using a copy I found in the app_usb_aud_xk_216_mc project since I could not find it in Install New Hardware.)

Any ideas what is going wrong?

[infiniteimprobability]

You're most of the way, and of course it should work OK!

 On tile 0, port F controls the mux and vbus control for USB. By default, D+ and D- won't reach the micro USB B connector. So you need to add this to get USB coming out to your port.

on tile[0]: out port port_4f = XS1_PORT_4F;

on tile[0]: {

    port_4f <: 0x7; //11 = USB B and VBUS enable

    while(1);

}

You need the while (1) or else the ports get de-init'ed on exit of the task. 
Give this a try...