High-speed DAPLink using ATSAM3U2C chip solution

product description

    This is a solution based on the official DAPLink implementation. The chip uses Atmel SAM3U2C/4C, with built-in USB high-speed phy, and the main frequency is 96Mhz. Currently, the official DAPLink solutions that support USB High Speed ​​include SAM3U2C, K26F, and LPC4322. Due to the current increase in chip prices, the disassembled SAM3U4C on Taobao is only 14 yuan each, so I chose the ATSAM3U solution.

    Two versions were designed. One uses the LQFP-100 package SAM3U4C-AU. There are many disassembled chips on Taobao and it is very cheap, but the size is slightly larger. The other uses the BGA-100 package SAM3U2C-CU, which is very small. Both versions have been board tested and verified to work normally. (I think BGA package is easier to solder than LQFP) Performance test can be found by searching high-speed DAPLink on Baidu. In addition, the firmware in the attachment only modifies the functional IO port and turns off the serial port flow control on the official version of DAPLink, and only has the SWD function. The JTAG function has reserved IO ports but has not been implemented.

Steps for usage

1. Download the code in the attachment. And the python3 environment is installed on the computer.
2. Use MDK to open the ..DAPLinkprojectfilesuvisionsam3u2c_blsam3u2c_bl.uvproj project. This is DAPLink's BootLoader.
3. Find line 37 of the IO_Config.h file and modify the IO definition based on the board you made (see the picture below). Compile after modification.
4. Use other Jlink or DAP devices to download the BootLoader into the chip. If everything is normal, connect the DAPLink to the USB, and a USB mobile storage device will appear on the computer.
5. Use MDK to open the ..DAPLinkprojectfilesuvisionsam3u2c_ifsam3u2c_if.uvproj project and compile it. This is the DAPLink application.
6. After successful programming, copy the ..DAPLinkprojectfilesuvisionsam3u2c_if uildsam3u2c_if.hex file to the USB mobile storage device that appears in step 3 (see the picture below). At this time, the DAP program will be automatically downloaded to the chip.
7. After the download is successful, it can be used normally. If you need to update the DAP firmware, you need to connect the NRST pin to ground and then plug it into the USB to proceed to step 5.
8. For compiling and burning DAPLink firmware, please refer to: DAPLink-Brochure: DAPLink Design and Application (Basics) (github.com)