[ISSUE] With 7.4.4 Sonoff Zdongle-e still failling

[zer013]

Hi. I flashed last version (7.4.4) in my Sonoff Zdongle-e and it still failling with error ERROR_EXCEEDED_MAXIMUM_ACK_TIMEOUT_COUNT.

Im using last version off Zigbee2MQTT (2.0.0-2) in my Home Assistant..

Thanks!

[Hedda]

@liangjia2019 I am not sure if this is the correct place to be reporting issues as you should instead probably be contacting ITead via their officially published support channels where you can open a new support ticket -> https://itead.freshdesk.com/support/home

Anyway, for reference relevant to this; there is currently a known bug with UART buffering (RX buffer) timeout issues when using software flow control with all the current versions of EmberZNet 7.4.x, 8.0.x, and 8.1.x that there is still no bug-fix available for.

Zigbee2MQTT/zigbee-herdsman developer Nerivec has reported a bug as an issue to upstream to Silicon Labs where he state that EmberZNet 7.4.x as well as all in all 8.0.x and 8.1.x have this issue where you can see UART buffering issues and "appears to have changed in a way that makes the NCP very unstable under load (like an ongoing OTA on the network), it will throw a lot of max ACK timeout count errors. A "mostly-working" workaround appears to be increasing the default SL_IOSTREAM_USART_VCOM_RX_BUFFER_SIZE from 32 to 128 or above. This affects mostly software flow control (so, unclear on 8.1.0 because of first point), and appears pre-dominantly on CP210x-driven modules.". See:

• Feedback on EmberZNet 8.1.0 SiliconLabs/simplicity_sdk#29

So that bug does affect all of the existing EFR32MG21-based Sonoff ZBDongle-E when using Zigbee Coordinator that has a CP2102N/CP2102 (CP210x) USB to UART Bridge VCP (which the early batches of Sonoff ZBDongle-E does not have). As he mentions; the only know workaround for now is to build a new firmware image that increase default SL_IOSTREAM_USART_VCOM_RX_BUFFER_SIZE from 32 to 128 (or above).

PS: FYI, Nerivec does provide unofficial experimental firmware builds on GitHub in his fork of Nabu Casa's silabs-firmware-builder:

• https://github.com/Nerivec/silabs-firmware-builder
  • https://github.com/Nerivec/silabs-firmware-builder/releases
    • https://github.com/Nerivec/silabs-firmware-builder/discussions

[zer013]

Thanks but i try nevirec experimental firmware and same problem..

Thanks!

[Hedda]

Thanks but i try nevirec experimental firmware and same problem.

Then suggest you post an issue to Zigbee2MQTT and detailed information on that as only their developers will be able to troubleshoot it -> https://github.com/Koenkk/zigbee2mqtt

[liangjia2019]

Thanks but i try nevirec experimental firmware and same problem..

Thanks!

Have you tried using ZHA to run dongle? Based on our experience, without modifying SL-IOSTREAM-USARRT_VCOM_SX_BUFFER_SIZE (default 32), did not see any errors when running in ZHA, but it appeared under Zigbee 2mqtt, it will throw a lot of max ACK timeout count errors.

[liangjia2019]

Thanks but i try nevirec experimental firmware and same problem..

Thanks!

Did you try nevirec experimental firmware SL-IOSTREAM-USARRT_VCOM_SX_BUFFER_SIZE=256,Although this is not the fundamental solution to the problem, does it have any effect on you.