Quectel AG35 Modem interfacing issue with SIM multiplexer

Technical Subjects Hardware Baseband
1

Hi ,

I am trying to interface Texas Instrument TXS02324 IC which is used for sim multiplexing.
I am communicating with this IC over I2C protocol. I am using nearly same api for the communication which was stated by Quectel itself.
While communicating with TI ic, SIM1 slot is selected by default by the IC. I am able to get the SIM CLK and SIMIO from baseband to SIM1. but when I switch the sim from SIM1 to SIM2, No clock is getting observed.

As per the IC datasheet, Baseband needs to be in clock stop mode before sim switching. Is there any such mode available.?
If Yes, Then how I can use this mode.

2

You can swap the SIM card with AT command

AT+QDSIM=0
AT+QDSIM=1

It cannot support Dual SIM at the same time.

3

Hi Mr. Wang

I am using Quectel AG35 series. I also have the AT command manual.

I couldn’t find the AT command which you shared.

Can you please suggest for this series of modem.

4

AT+QDSIM=0 // for SIM1
AT+QDSIM=1 // for SIM2

It might not mentioned in the AT manual.
Are you using the Quectel EVB?

It support one SIM card, if you want to switch to another SIM card you might need the AT command to swith the SIM card slot.

5

I am using EVB. It comes with esim. I had removed esim safely and used those tracks to connect with TI TXS02324 IC.

Now with this IC, sim slot 1 is working good when ever I start the modem or either I switch from sim slot 2 to sim 1.

When I start modem with sim slot 2 or I switch from sim1 to sim2, there is no communication from modem side. No clock is monitored in this situation.

6

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7

Using these AT Commands results into Error.

AT+QDSIM = 1
AT + QDSIM = 0

8

Does it support
AT+QDSIM?