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RFM95W

HopeRF RFM95W LoRa module (Semtech SX1276) as an SPI register shell. No RF air link.

Live catalog

Prefer labwired_describe with the catalog id over guessing pins or addresses.

Status at a glance

Aspect Status
Catalog id rfm95
Bus SPI (mode 0)
Address — (NSS via cs_pin)
Source configs/devices/rfm95.yaml (declarative, no Rust model)
Datasheet Semtech SX1276/77/78/79 rev. 4, §4.3 SPI Interface, §6.1 Table 41; HopeRF RFM95/96/97/98(W) V1
Tier smoke-proven (register-level tests: crates/core/tests/everyday_sensor_set.rs)

Pins / attachment

Pin / net Role
SCK / MOSI / MISO SPI
NSS cs_pin
DIO0..DIO5, RESET Not modelled
3.3V/GND Power (digital twin)

Support matrix

Behavior Status Notes
Address byte: bit 7 = write, bits 6:0 = address ✅
RegVersion 0x42 = 0x12, read-only ✅ The HopeRF V1 sheet prints 0x11 (earlier silicon)
Table 41 power-on values (RegOpMode 0x01, RegFrf 434 MHz, RegPaConfig 0x4F, …) ✅ FSK/OOK-mode values, as at power-on
Register storage (write, read back) ✅
Burst auto-increment ❌ One byte per address frame
FSK ⇄ LoRa register banking, mode sequencing ❌ 0x0D–0x3F keep what they hold when LongRangeMode is set
RF air link, packet engine, FIFO, DIO interrupts, RSSI ❌ A transmit never produces a packet; TxDone never fires

Stimulus

None — no measurement channel.

How to run

  1. Place the part and an MCU in Playground, or add it to a system YAML: 
    external_devices:
  - id: "lora"
    type: "rfm95"
    connection: "spi1"   # the SPI bus id your chip system uses
    config:
      cs_pin: "PA4"
  2. Agent: labwired_list → labwired_describe id=rfm95 → wire → labwired_validate → labwired_run / labwired_verify.
  3. Register-level smoke: cargo test -p labwired-core --test everyday_sensor_set — RegVersion, power-on RegOpMode / RegFrf / RegPaConfig / RegPaDac, and a RegOpMode write. The SPI negative control proves the check fails against a part that answers only 0x00 or only 0xFF; rfm95_tracks_stimulus stores a 915 MHz setup and checks RegVersion refuses a write.

Limitations

  • Use this to check that a driver probes and configures the radio. It cannot show a link working; for that, see the lora_sx1278 shell's notes in docs/part-packs.md.

See the YAML header for the full datasheet trace and every named approximation.