Hi,

I was working to reverse engineer the chip name: BM1398BB, the same chip used inside Bitminer S19 or S19 pro.

I already figured out the pinmaps and the hardware use of this ASIC. I already made a test pcb with the ASIC. I could reset the chip from the reset pin and also send a 25MHz signal. Even this signal coming out from the CLKO pin. When I am touching the reset pin with GND the current goes back to 1.9 A. But when I am making it high to 1.8V then the current consumption is increasing to 10A.  That proves my experimental hardware is working.

I was sending commands to the PIN: CI and was expecting the response out from: RO
Need to mention that I am using a level shifter IC to convert 1.8V level to 3.3V or vise versa

For sending commands I was following the workformat of BM1385 listed in the datasheet
But looking like the ASIC is not responding with the commands. I think they change their communication protocol for BM1398BB

Now, I was planning to check the software firmware from the Bitminer S19 machine. But I am not sure I will get the source code of the firmware.

Can anyone please help me out establishing communication with BM1398BB ASIC. And what is the protocol to send commands for tasks?