Anyone have success with parallel interface to either CH375 or CH376 USB devices ?

I've been playing with CH375 (hopefully this link to datasheet works for you: https://images.100y.com.tw/pdf_file/34-WCH-CH375.pdf.

I am using C8051F340 and the parallel interface to the board like this one: **broken link removed**

I believe I have communications proper as I can send command which results in an interrupt back from the device, then read from the device, and the interrupt is cleared - as described in the datasheet.

The problem is I have no confidence in any of the values I read - other then the return from the GET_IC_VER command (always a 01). The datasheet is not that clear about how to initialize it - I have tried a variety of commands in different order, and the only status value I can read back is 22 hex.

I have not bothered to try any of the other commands that return size, etc, thinking the most basic command should work before I move on. I've tried 3 boards, 4 USB FLASH drives (Fat32, 16), and a few mice, and keyboards. All the same - every status value read back is 22 hex.

I mistakenly ordered the 375s ... I am getting 376s soon - they have built in fat32 support.

I have tried varying delays in between command and status read, no change. I may try the serial interface as that is a bit simpler - datasheet suggests the only signals involved there are tx, rx, and INT (no address pin).

I have seen various code fragments online - nothing suggesting my procedures are invalid.

Appreciate any advice.

I saw a pinout of the jumpers of the CH376 board somewhere on this board but can't remember. The posting was incorrect and showed two of the pins as NC. I made the drawing below. It is the same for both the CH375 and CH376 boards.

A jumper would only be placed in one of the positions shown. If RS232 interface is selected, then the three lower pins would be used. The two pins on the far right are tied together, so the position of the jumper either ties TX to GND or routes it to the TX pin below.

Having more success using the serial interface to the CH375.

do you have any link for helping in ch375B for serial comm.?
for serial there are 3 pins tx , rx and interrupt pin