Specifications

VLSI
Solution
y
VS1053b
VS1053B
9. OPERATION
Gain Volume SCI VOL (Volume-Gain)
-11 (-5.5 dB) 0 (+0.0 dB) 0x0b0b (-5.5 dB)
-11 (-5.5 dB) 3 (-1.5 dB) 0x0e0e (-7.0 dB)
+2 (+1.0 dB) 0 (+0.0 dB) 0x0000 (+0.0 dB)
+2 (+1.0 dB) 1 (-0.5 dB) 0x0000 (+0.0 dB)
+2 (+1.0 dB) 4 (-2.0 dB) 0x0202 (-1.0 dB)
9.12 SDI Tests
There are several test modes in VS1053b, which allow the user to perform memory tests, SCI bus tests,
and several different sine wave tests.
All tests are started in a similar way: VS1053b is hardware reset, SM TESTS is set, and then a test
command is sent to the SDI bus. Each test is started by sending a 4-byte special command sequence,
followed by 4 zeros. The sequences are described below.
9.12.1 Sine Test
Sine test is initialized with the 8-byte sequence 0x53 0xEF 0x6E n 0 0 0 0, where n defines the sine test
to use. n is defined as follows:
n bits
Name Bits Description
F
s
Idx 7:5 Samplerate index
S 4:0 Sine skip speed
F
s
Idx F
s
F
s
Idx F
s
0 44100 Hz 4 24000 Hz
1 48000 Hz 5 16000 Hz
2 32000 Hz 6 11025 Hz
3 22050 Hz 7 12000 Hz
The frequency of the sine to be output can now be calculated from F = F
s
×
S
128
.
Example: Sine test is activated with value 126, which is 0b01111110. Breaking n to its components,
F
s
Idx = 0b011 = 3 and thus F
s
= 22050Hz. S = 0b11110 = 30, and thus the final sine frequency
F = 22050Hz ×
30
128
≈ 5168Hz.
To exit the sine test, send the sequence 0x45 0x78 0x69 0x74 0 0 0 0.
Note: Sine test signals go through the digital volume control, so it is possible to test channels separately.
9.12.2 Pin Test
Pin test is activated with the 8-byte sequence 0x50 0xED 0x6E 0x54 0 0 0 0. This test is meant for chip
production testing only.
Version 1.01, 2008-05-22 63