SPI AT Command frame always causes a Modem Status reply


We are evaluating the S2C module on our reference MCU platform (STM32) for possible use on a new product.

Module is XB24CAPIT-001 (CAPIS version will be used on the product)
Firwmare version is 2001
Hardware version is 2E

Interface is SPI (@2.5MHz) with ATTN on interrupt.

A frame is sent:
0x7E 0x00 0x04 0x08 0x06 0x43 0x48 0x66
ATTN is asserted around 150 us later.
When reading data I always see:
0x7e 0x00 0x02 0x8A 0x00 0x75

The same operation when using UART generates proper AT Command Response.
Is there anything wrong in our setup?

Check your CONFIG line to make sure you are not holding it low.

This was exactly what happened, thanks.