Hi, I have MB1329B module with quectel BG96 with firmware version: BG96MAR02A06M1G. I intend to send data by NB-IoT with a plastic sim card but it isn't working because the SIM is not detected.

[FCelm.1]

I have the PWR enable pin at high level, the sim_select1 pin also at high level and the sim_select0 pin at low level (because I have a plastic sim).

I'm sending the following AT Commands using usb connection directly between the module and a computer:

/* Use ATI to get module information of Manufacturer ID, Device module and Firmware version */

[2020-09-16 12:17:49:943_R:] ATI

[2020-09-16 12:17:49:943_R:] Quectel

[2020-09-16 12:17:49:943_R:] BG96

[2020-09-16 12:17:49:943_R:] Revision: BG96MAR02A06M1G

/* Use AT+CMEE=2 to enable result code and use verbose values */

[2020-09-16 12:17:50:552_R:] AT+CMEE=2

[2020-09-16 12:17:50:552_R:] OK

/* Use AT+GSN to query the IMEI of module */

[2020-09-16 12:17:51:146_R:] AT+GSN

[2020-09-16 12:17:51:146_R:] 866425030111175

[2020-09-16 12:17:51:786_R:] AT+CPIN?

[2020-09-16 12:17:51:786_R:] +CME ERROR: SIM not inserted

After sendig AT+CPIN? command the module responds thas sim is not inserted. Sim is inserted correctly and after doing some checks, I've seen that There isn't power supply in the sim connector (CN4) . Aparently, all config pins in the module are in the correct level and it would be very strange if it was a hardware problem.

Could you help me to solve this?

Thank you!

Ferran

[Mike_ST]

sim_select_1 is output enable /OE for the SN74CB3Q3257 (U6). It is active low. Try to maintain it to 0. Keeping it at 1 will disable connection between modem and the SIM cards.

sim_select_0, allows to select sim.

sim_select_0 = 0 plastic SIM

sim_select_0 = 1 eSIM

[FCelm.1]

Hello Mike,

I try to do it this way and the problem persists. With sim_select_1 and sim_select_0 at low level the sim isn't detected and there isn't power supply at SIM connector CN4.

The figure below is part of modul schematics and corresponds to multiplexer SN74CB3Q3257PW (U6)

Checking all pins with a multimeter I can see the power supply is OK, sim_select 1 and 2 are OK (both at low level) and the output VDD_SIM1 and VDD_SIM2 are both at 0, so this output is wrong. Is there something I have to do with pins sim_DATA, sim_RST and sim_CLK to obtain 1 at pins VDD_SIMx?

Thank you

[FCelm.1]

Sorry, here is the multiplexer image.

[Mike_ST]

VDD_SIMx is given by VDD_SIM, which comes from the BG96 module.

So... I'm not sure what is happening there.

>> I'm sending the following AT Commands using usb connection directly between the module and a computer:

Our main use case was with the 20 pins connector, not USB. PWR_EN and RESET had to be driven at power up:

Please try these timings for the reset sequence, I used that few years ago:

 HAL_GPIO_WritePin(RESET_PORT, RESET_PIN, GPIO_PIN_SET);

 HAL_Delay(200);

 HAL_GPIO_WritePin(RESET_PORT, RESET_PIN, GPIO_PIN_RESET);

 HAL_Delay(150);

 HAL_GPIO_WritePin(POWER_PORT, POWER_PIN, GPIO_PIN_SET);

 HAL_Delay(150);

 HAL_GPIO_WritePin(POWER_PORT, POWER_PIN, GPIO_PIN_RESET);

and wait for "RDY" message.

[FCelm.1]

I've done manually the pin pull-up and pull-down sequence shown above and it isn't working, may be there is a HW problem, but I have two modules and I have the same problem in both.