LISA-U2 series - System integration manual
UBX-13001118 - R27
System description
Page 93 of 183
C1-Public
The I2S interface can be set to two modes using the <I2S_mode> parameter of the AT+UI2S
command:
•
PCM mode
•
Normal I2S mode
The I2S interface can be set to two configurations, by the <I2S_host_local_device> parameter of
AT+UI2S:
•
Host mode
•
Local device mode
The sample rate of transmitted/received words can be set, by the <I2S_sample_rate> parameter of
AT+UI2S, to:
•
8 kHz
•
11.025 kHz
•
12 kHz
•
16 kHz
•
22.05 kHz
•
24 kHz
•
32 kHz
•
44.1 kHz
•
48 kHz
The <main_uplink> and <main_downlink> parameters of the AT+USPM command must be properly
configured to select the I2S digital audio interfaces paths (for more details, see the u-blox AT
commands manual
•
<main_uplink> must be properly set to select:
o
the first I2S interface (using
I2S_RXD
module input)
o
the second I2S interface (using
I2S1_RXD
module input)
•
<main_downlink> must be properly set to select:
o
the first I2S interface (using
I2S_TXD
module output)
o
the second I2S interface (using
I2S1_TXD
module output)
Parameters of the digital path can be configured and saved as the normal analog paths, using
appropriate path parameters as described in the u-blox AT commands manual
, +USGC, +UMGC,
+USTN AT command. Analog gain parameters are not used.
The I2S receive data input and the I2S transmit data output signals can use the following resources:
•
Digital filters and digital gains are available in both uplink and downlink directions. They can be
correctly configured with the AT commands
•
Ringer tone and service tone are mixed on the TX path when active (downlink)
•
The HF algorithm acts on the I2S path
☞
See the u-blox AT commands manual
(AT+UI2S command) for the possible settings of the I2S
interface.
