USB Audio Design Guide
This function simply makes a call to
mic_array_get_next_time_domain_frame()
in
order to get a frame of PCM audio from the microphones. It then waits for an
request for audio samples from the audio/I2S/TDM core via a channel and sends
the frame of audio back over this channel.
Note, it is assumed that the system shares a global master-clock, therefore no
additional buffering or rate-matching/conversion is required.
3.14
Resource Usage
The following table details the resource usage of each component of the reference
design software.
Component
Cores
Memory (KB)
Ports
XUD library
1
9 (6 code)
ULPI ports
Endpoint 0
1
17.5 (10.5 code)
none
USB Buffering
1
22.5 (1 code)
none
Audio driver
1
8.5 (6 code)
See §
S/PDIF Tx
1
3.5 (2 code)
1 x 1 bit port
S/PDIF Rx
1
3.7 (3.7 code)
1 x 1 bit port
ADAT Rx
1
3.2 (3.2 code)
1 x 1 bit port
Midi
1
6.5 (1.5 code)
2 x 1 bit ports
Mixer
2
8.7 (6.5 code)
ClockGen
1
2.5 (2.4 code)
Figure 27:
Resource
Usage
These resource estimates are based on the multichannel reference design with all
options of that design enabled. For fewer channels, the resource usage is likely to
decrease.
The XUD library requires an 80MIPS core to function correctly (i.e. on a 500MHz
part only six cores can run).
The ULPI ports are a fixed set of ports on the L-Series device. When using these
ports, other ports are unavailable when ULPI is active. See the XS1-L Hardware
Design Checklist
21
for further details.
http://www.xmos.com/published/xs1lcheck
XM0088546.1
Summary of Contents for xCORE-200 Multi-channel Audio board
Page 6: ...1 Overview XM0088546 1...
