Integration Manual

Table Of Contents
LISA-U2 series - System Integration Manual
UBX-13001118 - R25 Features description Page 153 of 182
Device including LISA
GSM/UMTS
Interface
SAP
Serial Interface
(USB SAP channel,
or MUX SAP channel
over UART or SPI)
Local SIM
(optional)
LISA module
SAP Client
Application
Processor
Device including SIM
SAP
Serial Interface
Remote SIM
Mobile
Equipment
SAP Server
Figure 70: Remote SIM access via completely wired connection
As stated in the SIM Access Profile Interoperability Specification [21], the SAP client can be connected
to the SAP server by means of a Bluetooth cellular link, using additional Bluetooth transceivers. In this
case, the application processor wired to the LISA-U2 modules establishes and controls the Bluetooth
connection using the SAP profile, and routes data received over a serial interface channel to data
transferred over a Bluetooth interface and vice versa, as shown in Figure 71.
Device including LISA
SAP
Serial Interface
(USB SAP channel,
or MUX SAP channel
over UART or SPI)
GSM/UMTS
Interface
Local SIM
(optional)
LISA module
SAP Client
Application
Processor
SAP
Bluetooth
Interface
Bluetooth
Transceiver
Device including SIM
Remote SIM
Mobile
Equipment
SAP Server
Bluetooth
Transceiver
Figure 71: Remote SIM access via Bluetooth and wired connections
The application processor can start an SAP connection negotiation between the LISA-U2 module SAP
client and an SAP server using a custom AT command (for more details, see the u-blox AT Commands
Manual [2]).
While the connection with the SAP server is not fully established, the LISA-U2 module continues to
operate with the attached (local) SIM, if present. Once the connection is established and negotiated,
the LISA-U2 module performs a detach operation from the local SIM followed by an attach operation
to the remote one. Then the remotely attached SIM is used for any GSM/UMTS network operation.
URC indications are provided to inform the user about the state of both the local and remote SIM. The
insertion and the removal of the local SIM card are notified if a proper card presence detection circuit
using the GPIO5 of LISA-U2 modules is implemented as shown in the section 1.8.1, and if the related
“SIM card detection” and “SIM hot insertion/removal” functions are enabled by AT commands (for
more details, see the u-blox AT Commands Manual [2], +UGPIOC, +UDCONF=50 AT commands).
Upon SAP deactivation, the LISA-U2 modules perform a detach operation from the remote SIM
followed by an attach operation to the local one, if present.