Integration Manual

LISA-U2 series - System Integration Manual
UBX-13001118 - R25 System description Page 93 of 182
The I
2
S interface can be set to two modes using the <I2S_mode> parameter of the AT+UI2S
command:
 PCM mode
 Normal I
2
S mode
The I
2
S interface can be set to two configurations, by the <I2S_Master_Slave> parameter of AT+UI2S:
 Master mode
 Slave 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 I
2
S digital audio interfaces paths (for more details, see the u-blox AT
Commands Manual [2]):
 <main_uplink> must be properly set to select:
o the first I
2
S interface (using I2S_RXD module input)
o the second I
2
S interface (using I2S1_RXD module input)
 <main_downlink> must be properly set to select:
o the first I
2
S interface (using I2S_TXD module output)
o the second I
2
S 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 [2], +USGC, +UMGC,
+USTN AT command. Analog gain parameters are not used.
The I
2
S receive data input and the I
2
S 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 I
2
S path
☞ See the u-blox AT Commands Manual [2] (AT+UI2S command) for the possible settings of the I
2
S
interface.