CC1120EMK-868-915: Issue with Replacing RF Module – Communication Not Established with Main Board

Hello everyone,

Our organization had previously outsourced the development of a custom RF module to a vendor for establishing wireless communication between the controller and sensors in a weighbridge system. The module was designed to wirelessly transmit weight data, which is then converted to RS485 and RS232 formats.

Unfortunately, the original vendor is no longer supporting or supplying the wireless boards. The wireless system comprises a main mcu board and RF module connected through SPI

To continue operations, we purchased a Chinese-made RF module that uses the same chip as the original one. However, after integrating this new module with our existing main board, the wireless communication fails to establish.

Here are the key differences between the old working RF board and the new one.

"Misses two ferrite best and a zenor diode connected to the 32mhz TCXO oscillator.

1. Dedicated HGM pin – Connected to 3.3V on the old board.

2. Dedicated TXCO – Also connected to 3.3V on the old board.

Additionally, the supplier of the Chinese RF module mentioned that a 5ms delay is required before issuing a reset. To my knowledge, our current firmware does not implement this delay (please correct me if I’m wrong—I'm relatively new to embedded systems).

Unfortunately, our organization doesn’t have any in-house firmware developers, so making firmware-level changes is not straightforward.

My main question:

Is it possible for this new RF board to work with our existing main board, given the above differences?
I've attached images of both the old and new RF boards for reference.

Any help or suggestions on what we should check or modify (hardware or firmware-wise) would be greatly appreciated.

Thanks in advance!