In f79f2f7 I have described the TD-4277 protocol, but I have no way to compare my mmol/L device with a mg/dL device to identify the glucose unit used by the device.
My best guesses are in model-response (the two undefined OCTET entries) or as part of record-value-response.
Either a usbmon trace of the data download, or a glucometerutils log with --vlog 5 would help answer the question.