The operator pushed back on calling this solved, correctly. Adjusting the wording
to match what the evidence actually carries.
What IS supported: on this bench setup, the modem and cable work bidirectionally
(laptop round trip, 700 ms), the same cable/modem pairing answers for a laptop and
not for the Micromate, and neither firmware image contains a Prolific driver.
Observation plus mechanism.
What is NOT: that this explains the field failures. Those cables cannot be
inspected, and the timeline does not fit -- a wrong cable fails from the first
packet, and that unit reportedly worked before degrading.
A gap in the bench claim itself, now stated: "no driver" is inferred from ABSENCE
of strings. usbHostDelete_* reads like a complete per-class list, which is good
evidence, but driver code can exist without a matching string and the USB
enumeration path has not been disassembled.
Names the test that removes the inference entirely: try an FTDI cable (VID 0403)
on the same modem. Either it works or it does not.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Ru8Lg9HkkYvX9VWWo65SmL
serversdownandClaude Opus 5
8a0134070b