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EmberZNet and EZSP Reference

This page clarifies the differences between various firmware modes (NCP, RCP), the role of EmberZNet, and the meaning of EZSP versions — common sources of confusion when flashing or configuring Zigbee firmware.

🧠 What is EmberZNet?

EmberZNet is Silicon Labs’ official Zigbee stack. It provides:

  • IEEE 802.15.4 MAC and PHY
  • Zigbee Network layer (routing, addressing)
  • Zigbee Application layer (clusters, ZCL)
  • Security and commissioning logic

It can run in multiple modes:

✅ SoC Mode

  • Full Zigbee stack and application run on the EFR32 chip.
  • No external host required.

✅ NCP Mode (Network Co-Processor)

  • The Zigbee stack runs on the EFR32.
  • An external Linux host communicates via EZSP protocol over UART.

✅ RCP Mode (Radio Co-Processor)

  • Only PHY and MAC run on the EFR32.
  • The Zigbee or Thread stack runs on the Linux host.
  • Requires CPC daemon (cpcd) on host.

🔌 What is EZSP?

EZSP = Ember Zigbee Serial Protocol

It is a binary protocol developed by Silicon Labs to control a Zigbee NCP over a serial link.

The Linux host communicates with the NCP using EZSP commands for:

  • Forming/joining a Zigbee network
  • Sending/receiving messages
  • Managing clusters, endpoints
  • Security, stack control

🧾 EZSP Versions

EmberZNet Version EZSP Version Notes
6.5.x.x V7 Found in original Lidl firmware
6.7.x.x V8 Used in Paul Banks’ project
7.4.x.x V13 Compatible with ember adapter in Z2M and ZHA

🧩 Compatibility with Zigbee2MQTT and ZHA

Zigbee2MQTT

EZSP Version Z2M Adapter
V7/V8 ezsp (deprecated)
V13+ ember (recommended) 
# Zigbee2MQTT example
serial:
  port: tcp://192.168.1.88:8888
  adapter: ember

Home Assistant (ZHA)

ZHA supports all EZSP versions but recommends EZSP V13+ for recent stacks.

📦 Available Firmware Versions

  • 🔸 EZSP V8:\ Used to update Paul Banks hack with a firmware provided by Gary Robas: Download .gbl

  • 🔸 EZSP V13:\ Built from Simplicity Studio Gecko SDK 4.4.x, they provide the most recent EMberZNet 7.4.x versions available at the time of this writing. See NCP-UART-HW section

🛑 Important Notes

  • EZSP is not compatible with RCP firmwares (use CPC instead).
  • Z2M is phasing out support for ezsp adapter; prefer ember.
  • The firmware must match the hardware pinout (PA0/PA1/etc.).

📚 References