I have an issue where the HL7812 reports bInterfaceProtocol 0 None on the USB interfaces. This is not supported by the cdc_acm driver in our legacy Debian Wheezy products. If we have to, I can go down patching the kernel - but would prefer not to. If it is an oversight in the module, could it be …

Just checking the latest source code (for Ubuntu) it has: /* control interfaces without any protocol set */ { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, USB_CDC_PROTO_NONE) }, This isn’t in the older Debian Wheezy driver. Modifying the kernel may be our only option - but a pain t…

HL7812 USB Descriptors

IoT Modules HL78

mark.bewley July 10, 2023, 10:28am 5

Yes, using a lot older version of Linux (on embedded device).
HL7812 on Debian Wheezy.txt

HL7812 USB failure

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HL7812 USB Descriptors

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