@Kabeer Makkar Below is the response received from our team on this issue.
Only certified devices appear in the list, Mxchip did not go through this process for V2 version of DTDL hence its not there.
The mxchip https://github.com/Azure/iot-plugandplay-models/blob/main/dtmi/azurertos/devkit/gsgmxchip-1.json will work with the Azure RTOS sample https://github.com/azure-rtos/getting-started/tree/master/MXChip/AZ3166 and can be used for lab or demo.
The template can be created by importing capability model from the repo. IoT Central will automatically create matching template if the modelId is sent by the device during registration. The above sample code does that.
Hope this answers your query. Do let us know if you have any further queries.
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