文章簡介
本文將說明如何在 Linux 主機上，於價格實惠且功能強大的 NXP FRDM-MCXN236 開發板上執行 Zephyr RTOS。透過實際範例，包含 Hello World、LED 閃爍 (Blinky) 以及執行緒同步 (Synchronization) 範例，快速驗證 Zephyr RTOS 在 FRDM-MCXN236 平台上的開發流程。
NXP FRDM-MCXN236 開發板簡介
NXP FRDM-MCXN236 開發板 搭載 32-bit Arm Cortex-M33 微控制器，適用於工業與消費級物聯網（IoT）應用。
FRDM-MCXN236 開發板方塊圖如下：
安裝 NXP LinkServer
完成 Zephyr 開發環境安裝後（安裝方式可參考前述 Zephyr Linux 安裝文章），接著需從 NXP 官方網站下載並安裝 LinkServer：
LinkServer 將用於後續燒錄（Flash）流程。
安裝完成後，可透過以下指令確認版本：
DigiKey_Coffee_Cup: /usr/local/LinkServer/LinkServer --version
ls (uutils coreutils) 0.8.0
驗證開發板連線
使用隨附 USB 線將開發板透過 J10 USB 埠連接至主機後，執行：
DigiKey_Coffee_Cup: /zephyrproject/zephyr$ LinkServer probes
# Description Serial Device Board Capabilities
--- --------------------------------------------- ------------- -------- ------------ ----------------
1 MCU-LINK FRDM-MCXN236 (r0E7) CMSIS-DAP V3.146 NTHJHYIGWSDV5 MCXN236 FRDM-MCXN236 DEBUG, VCOM, SIO
修改 Hello World 範例
編輯 samples/hello_world/src/main.c
修改內容如下：
/*
* Copyright (c) 2012-2014 Wind River Systems, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <stdio.h>
int main(void)
{
printf("DigiKey_Coffee_Cup Hello World! %s\n", CONFIG_BOARD_TARGET);
return 0;
}
建置 Hello World
於 Python Virtual Environment 中執行，及建置完成後可看到：
(venv) DigiKey_Coffee_Cup: /zephyrproject/zephyr/ west build -b frdm_mcxn236 samples/hello_world
...
...
v4.4.0-8487-g17939cff6553
[168/168] Linking C executable zephyr/zephyr.elf
Memory region Used Size Region Size %age Used
FLASH: 27504 B 1 MB 2.62%
RAM: 4328 B 192 KB 2.20%
SRAM1: 0 B 96 KB 0.00%
IDT_LIST: 0 B 32 KB 0.00%
燒錄 Hello World
開啟新的終端機並啟動 minicom。
接著執行，及輸出內容如下：
(venv) DigiKey_Coffee_Cup: /zephyrproject/zephyr$ west flash
-- west flash: rebuilding
ninja: no work to do.
-- west flash: using runner linkserver
RUNNER - gdb_port = 3333, semih port = 8888
LinkServer: /usr/local/LinkServer/LinkServer, version v26.6.137
INFO: Exact match for MCXN236:FRDM-MCXN236 found
INFO: Selected device MCXN236:FRDM-MCXN236
INFO: Selected probe #1 NTHJHYIGWSDV5 (MCU-LINK FRDM-MCXN236 (r0E7) CMSIS-DAP V3.146)
INFO: MCU-Link firmware update `check`: Probe ([NTHJHYIGWSDV5] [MCU-LINK FRDM-MCXN236 (r0E7) CMSIS-DAP V3.146]) is running a firmware version which is older than the included firmware version [3.172]
INFO: Selected device matches probe's target identification info
minicom 顯示：
Welcome to minicom 2.10
OPTIONS: I18n
Port /dev/ttyACM0, 08:34:37 [U]
Press CTRL-A Z for help on special keys
*** Booting Zephyr OS build v4.4.0-8487-g17939cff6553 ***
DigiKey_Coffee_Cup Hello World! frdm_mcxn236/mcxn236
建置與執行 Blinky 範例
建置 LED 範例：
(venv) DigiKey_Coffee_Cup: west build -b frdm_mcxn236 samples/basic/blinky
...
...
[168/168] Linking C executable zephyr/zephyr.elf
Memory region Used Size Region Size %age Used
FLASH: 27580 B 1 MB 2.63%
RAM: 4328 B 192 KB 2.20%
SRAM1: 0 B 96 KB 0.00%
IDT_LIST: 0 B 32 KB 0.00%
編譯完成後執行：
(venv) DigiKey_Coffee_Cup: west flash
-- west flash: rebuilding
ninja: no work to do.
-- west flash: using runner linkserver
RUNNER - gdb_port = 3333, semih port = 8888
LinkServer: /usr/local/LinkServer/LinkServer, version v26.6.137
INFO: Exact match for MCXN236:FRDM-MCXN236 found
INFO: Selected device MCXN236:FRDM-MCXN236
INFO: Selected probe #1 NTHJHYIGWSDV5 (MCU-LINK FRDM-MCXN236 (r0E7) CMSIS-DAP V3.146)
INFO: MCU-Link firmware update `check`: Probe ([NTHJHYIGWSDV5] [MCU-LINK FRDM-MCXN236 (r0E7) CMSIS-DAP V3.146]) is running a firmware version which is older than the included firmware version [3.172]
INFO: Selected device matches probe's target identification info
minicom 顯示：
*** Booting Zephyr OS build v4.4.0-8487-g17939cff6553 ***
LED state: OFF
LED state: ON
LED state: OFF
LED state: ON
LED state: OFF
LED state: ON
LED state: OFF
LED state: ON
...
...
以下影片顯示 NXP FRDM-MCXN236 開發板 RGB LED 的 Zephyr Blinky 範例執行情況。
建置與執行 Synchronization 範例
建置 Synchronization 範例, 及建置完成後：
(venv) DigiKey_Coffee_Cup: zephyrproject/zephyr$ west build -b frdm_mcxn236 samples/synchronization
...
...
...
[168/168] Linking C executable zephyr/zephyr.elf
Memory region Used Size Region Size %age Used
FLASH: 28472 B 1 MB 2.72%
RAM: 6824 B 192 KB 3.47%
SRAM1: 0 B 96 KB 0.00%
IDT_LIST: 0 B 32 KB 0.00%
保持 minicom 開啟並執行：
/zephyrproject/zephyr$ west flash
-- west flash: rebuilding
ninja: no work to do.
-- west flash: using runner linkserver
RUNNER - gdb_port = 3333, semih port = 8888
LinkServer: /usr/local/LinkServer/LinkServer, version v26.6.137
INFO: Exact match for MCXN236:FRDM-MCXN236 found
INFO: Selected device MCXN236:FRDM-MCXN236
INFO: Selected probe #1 NTHJHYIGWSDV5 (MCU-LINK FRDM-MCXN236 (r0E7) CMSIS-DAP V3.146)
INFO: MCU-Link firmware update `check`: Probe ([NTHJHYIGWSDV5] [MCU-LINK FRDM-MCXN236 (r0E7) CMSIS-DAP V3.146]) is running a firmware version which is older than the included firmware version [3.172]
INFO: Selected device matches probe's target identification info
minicom 將顯示：
*** Booting Zephyr OS build v4.4.0-8487-g17939cff6553 ***
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
thread_b: Hello World from cpu 0 on frdm_mcxn236!
thread_a: Hello World from cpu 0 on frdm_mcxn236!
...
...
此結果顯示 Zephyr Kernel 的排程、通訊與計時機制正常運作。
FRDM-MCXN236 開發板功能
FRDM-MCXN236 是基於 MCX N236 元件設計的低成本開發與評估平台，搭載 Winbond 64 Mbit 外部序列式快閃記憶體。
板載功能包括：
- High-Speed USB
- Accelerometer Sensor
- CAN PHY
- Audio Codec (DNP)
- DMIC Sensor
- RGB LED
- Push Buttons
- MCU-Link Debug Probe
此外，開發板亦支援：
以及相容的相機模組與 LCD 模組。
結語
本文示範如何在 Linux 主機上使用 Zephyr RTOS，並於 NXP FRDM-MCXN236 開發板上執行 Hello World、Blinky 與 Synchronization 範例。
FRDM-MCXN236 是一款精巧且可擴充的開發平台，可用於 MCX N23X MCU 的快速原型開發與評估，並已於 DigiKey 提供相關產品資訊。