87
Table 6-4 Slide switch setting for sample rate switching for audio recorder and player
SW4
(0 – DOWN;
1- UP)
SW3
(0 – DOWN;
1-UP)
SW2
(0 – DOWN;
1-UP)
Sample Rate
0
0
0
96K
0
0
1
48K
0
1
0
44.1K
0
1
1
32K
1
0
0
8K
Unlisted combination
96K
Note:
(1). Execute
C5G_Audio
\demo_batch\
C5G_Audio
.bat will download .sof and .elf files.
(2). Recording process will stop if audio buffer is full.
(3). Playing process will stop if audio data is played completely.
6
6
.
.
6
6
M
M
i
i
c
c
r
r
o
o
S
S
D
D
C
C
a
a
r
r
d
d
f
f
i
i
l
l
e
e
s
s
y
y
s
s
t
t
e
e
m
m
r
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e
e
a
a
d
d
Many applications use a large external storage device, such as an SD Card or CF card to store data.
The C5G board provides the hardware and software needed for Micro SD Card access. In this
demonstration we will show how to browse files stored in the root directory of an SD Card and how
to read the file contents of a specific file. The Micro SD Card is required to be formatted as FAT
File System in advance. Long file name is supported in this demonstration.
shows the
hardware system block diagram of this demonstration. The system requires a 50MHz clock
provided by the board. The PLL generates a 100MHz clock for the Nios II processor and other
controllers. Four PIO pins are connected to the Micro SD Card socket. SD 4-bit Mode is used to
access the Micro SD Card hardware. The SD 4-bit protocol and FAT File System function are all
implemented by Nios II software. The software is stored in the on-chip memory.
