Request AudioReQuest N.Series Handbuch PDF herunterladen (Seite 56)

USB Audio Design Guide 56/61

chanend ?c_sof,

XUD_EpType epTypeTableOut[],

XUD_EpType epTypeTableIn[],

out port ?p_usb_rst,

clock ?clk,

unsigned rstMask,

unsigned desiredSpeed,

chanend ?c_usb_testmode)

This performs the low level USB I/O operations.

Note that this needs to run in a thread with at least 80 MIPS worst case execution

speed.

This function has the following parameters:

c_ep_out

An array of channel ends, one channel end per output endpoint

(USB OUT transaction); this includes a channel to obtain requests

on Endpoint 0.

num_out

The number of output endpoints, should be at least 1 (for Endpoint

0).

c_ep_in

An array of channel ends, one channel end per input endpoint (USB

IN transaction); this includes a channel to respond to requests on

Endpoint 0.

num_in

The number of input endpoints, should be at least 1 (for Endpoint

0).

c_sof

A channel to receive SOF tokens on. This channel must be connected

to a process that can receive a token once every 125 ms. If tokens

are not read, the USB layer will block up. If no SOF tokens are

required null should be used as this channel.

ep_type_table_out

See ep_type_table_in

ep_type_table_in

This and ep_type_table_out are two arrays indicating the type of

channel ends. Legal types include:

XUD_EPTYPE_CTL

(Endpoint 0),

XUD_EPTYPE_BUL

(Bulk endpoint),

XUD_EPTYPE_ISO

(Isochronous end-

point),

XUD_EPTYPE_DIS

(Endpoint not used). The ﬁrst array contains

the endpoint types for each of the OUT endpoints, the second array

contains the endpoint types for each of the IN endpoints.

p_usb_rst The port to send reset signals to.

clk

The clock block to use for the USB reset - this should not be clock

block 0.

REV 6.1

1 2 ... 51 52 53 54 55 56 57 58 59 60 61 62

Kommentare zu diesen Handbüchern

Keine Kommentare

Request AudioReQuest N.Series Handbuch Seite 56

Kommentare zu diesen Handbüchern