关于SAMD21G18自定义板ATMEL-ICE额外引脚连接的技术问询

Great question! Let's walk through how to handle the remaining pins on your ATMEL-ICE when connecting to the SAMD21G18 custom board, building on the connections you've already mapped out.

Key Remaining Pin Connections #

• VTREF: This is a required connection. Link it to your target board's VDDIN (same power rail as your existing VCC connection). The ATMEL-ICE uses this pin to detect that the target board is powered up, which is critical for establishing a stable SWD communication link.
• SWO (Serial Wire Output): This is optional. If you plan to use debug tracing features (like redirecting printf output or instruction trace), connect this pin to the SAMD21G18's PA24 pin (its dedicated SWO function). If you don't need tracing functionality, you can leave this pin unconnected.
• JTAG-specific pins (TCK, TMS, TDI, TDO): Since you're using SWD mode (which only requires SWCLK, SWDIO, nReset, VTREF, and GND), these pins are entirely unnecessary. You can leave them disconnected without affecting programming or basic debugging.

Important Notes #

• Double-check that your target board's VDDIN voltage is within the ATMEL-ICE's supported range (1.65V to 5V). The SAMD21G18 runs on 3.3V, which falls well within this range.
• Avoid connecting the ATMEL-ICE's 5V pin to your SAMD21G18 board—this will damage the 3.3V-only microcontroller.
• If your custom board includes an external reset circuit, the nReset connection you've already planned will still work seamlessly; the ATMEL-ICE can assert reset to initiate programming/debug sessions.

内容的提问来源于stack exchange，提问作者Hasan alattar