Seeed provided me with XIAO nRF54LM20A samples. One unit is mounted on the GPIO breakout board for XIAO. I soldered the battery connections and the JLink wiring.
If you’re using it as a hobby project, you can start writing sketches right away in the Arduino IDE without having to go through the trouble of setting up a Zephyr development environment.
Using the nrf54-arduino-core currently under development by @Loren_Bufamu, I wrote a sketch that might serve as a useful reference.
200-Byte Bidirectional Communication via BLE Notify/Write Using codedPHY
This sketch performs bidirectional communication of up to 244 bytes using 1M PHY, 2M PHY, and codedPHY. It uses the nPM1300 to measure battery voltage.
12:47:49.475 →
12:47:50.296 → conn_hdl = 0, PHY = 4, Data length = 251, MTU = 247, Interval =40
12:47:50.296 → Peripheral timestamp = 75, vbat = 0.019 V
12:47:50.296 → C4 27 01 00 E3 A5 9B 3C 08 09 0A 0B 0C 0D 0E 0F | .‘…<…
12:47:50.296 → 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F | …
12:47:50.296 → 20 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F | !"#$%&’()*+,-./
12:47:50.296 → 30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F | 0123456789:;<=>?
12:47:50.296 → 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F | @ABCDEFGHIJKLMNO
12:47:50.296 → 50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F | PQRSTUVWXYZ^_
12:47:50.296 → 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F | `abcdefghijklmno
12:47:50.296 → 70 71 72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F | pqrstuvwxyz{|}~.
12:47:50.296 → 80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F | …
12:47:50.296 → 90 91 92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F | …
12:47:50.296 → A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF | …
12:47:50.296 → B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 BA BB BC BD BE BF | …
12:47:50.296 → C0 C1 C2 C3 C4 C5 C6 C7 C8 C9 CA CB CC CD CE CF | …
12:47:50.296 → D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 DA DB DC DD DE DF | …
12:47:50.296 → E0 E1 E2 E3 E4 E5 E6 E7 E8 E9 EA EB EC ED EE EF | …
12:47:50.296 → F0 F1 F2 F3 | …
12:47:50.494 → Central timestamp = 84, rssi = -27.70 dBm
12:47:50.494 →
nRF54LM_XIAO_NotifyWrite_Peripheral.zip (2.9 KB)
nRF54LM_XIAO_NotifyWrite_Central.zip (2.7 KB)
Attitude Monitor Using the Built-in IMU
This sketch calculates attitude based on data from the built-in IMU. The IMU is powered by the nPM1300’s LDO.
nRF54LM_XIAO_AttMonitor_AdaLib.zip (2.2 KB)
