DAP writer

I hope I am at the right place.
I used some old design I found out on the internet a few years ago, to make an Ameba Realtek writer. My goal is to use it for uploading sketches through Arduino IDE. But, I get stuck at the very first step.

This is the schematic.
As I was short of some components I used 22pF instead of 20pF for C2 and C3 and 1.8K instead of 1.5K for R5. The rest is as it is.

When I plug this board into a PC I can see it in my Device Manager as unrecognized (unknown). So far so good.

The next step is to upload a new firmware from an Amebaiot site. To do so, I need to put it in a drive mode with two buttons. This is the place I stuck. By clicking buttons as it shows on the site I provide, it cannot mount as a drive.


What I mess up?

This looks interesting, I assume that the target device is the RTL8195 module?

I am not familiar with the DAP, but comparing your schematic with that found at Ameba1 – Realtek IoT/Wi-Fi MCU Solutions, it seems like there are some differences in the DAP portion of the schematic, not sure if this will cause any issues.

Are you starting with a blank LPC11U35 chip? I have a guess that the chip itself may need a bootloader or some lower level firmware, in order to enable the two button drive mode to update firmware.

Are you programming RTL8710AF?

I am stuck on firmware. I can not put this DAP into USB device so I can upload firmware on it. In my opinion, it could be wrong schematic, bad soldering or something else.

RTL8710 is the goal, but for now, it is way ahead.

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Did you follow design of this project?

I know I found it somewhere. But couldn’t remember where. That is the one.

Anyway, the problem persists.

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maybe this is what you looking for
CMSIS-DAP Debugger User's Guide: About CMSIS-DAP.

The problem is I can not mount DAP as a USB device to upload the firmware.
Could it be because of these few changed components?
On the link I provide, it says all about the procedure. All I need is 2 buttons, which I have. But it still doesn"t mount as a USB device.

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