Discover the Millennia eV port by its STM32 USB-CDC VID/PID#108
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Problem: MillenniaEv25Device could only be constructed with an explicit portPath; doInitializeDevice opened SerialPort(portPath=...) and never fell back to VID/PID discovery, so a caller (e.g. the MillenniaUI app) had to know the OS port name up front. The class did not set classIdVendor/classIdProduct, so nothing identified the device by its USB descriptor. Solution: Set classIdVendor = 0x0483 / classIdProduct = 0x5740 (the STM32 Virtual COM Port identity the lab eV25s enumerates as) and have doInitializeDevice discover the port by that identity when no portPath is given, mirroring FieldMasterDevice: it builds SerialPort(idVendor, idProduct, serialNumber) -> matchAnyPort over pyserial's comports(), and raises a clear UnableToInitialize naming the identity when nothing matches. An explicit portPath still wins; a serialNumber narrows discovery when several STM32 CDC ports are present. serialNumber is passed only when it actually narrows, so matchPorts stays on its vid/pid path and never regex-matches a possibly-None descriptor serial. The generic-STM32-VCP caveat is documented in the code. DebugMillenniaEv25Device is unaffected: it overrides doInitializeDevice and keeps its own fake identity. testMillennia.py passes (14 passed, 6 skipped). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Problem
MillenniaEv25Devicecould only be constructed with an explicitportPath—doInitializeDeviceopenedSerialPort(portPath=...)and never fell back to VID/PID discovery. A caller (e.g. the MillenniaUI app) had to know the OS port name up front, and the class set noclassIdVendor/classIdProductto identify the device.Solution
classIdVendor = 0x0483/classIdProduct = 0x5740— the STM32 Virtual COM Port identity the lab eV25s enumerates as (confirmed on the bench).doInitializeDevicenow discovers the port by that identity when noportPathis given, mirroringFieldMasterDevice: it buildsSerialPort(idVendor, idProduct, serialNumber)→matchAnyPortover pyserial'scomports(), and raises a clearUnableToInitializenaming the identity when nothing matches.Precedence for the UI:
MillenniaDevice(portPath=...)→ uses that exact port (still wins).MillenniaDevice()→ auto-discovers by0x0483:0x5740.MillenniaDevice(serialNumber="3239")→ discovery narrowed by USB descriptor serial (for hosts with more than one STM32 CDC port).serialNumberis forwarded only when it actually narrows, somatchPortsstays on its vid/pid path and never regex-matches a possibly-Nonedescriptor serial.Caveat (documented in code)
0x0483:0x5740is STMicro's generic STM32 VCP identity, shared by many unrelated STM32 boards. On a host with another STM32 CDC device, discovery could bind to the wrong port — pinportPath(or passserialNumber) there.Tests
DebugMillenniaEv25Deviceis unaffected (it overridesdoInitializeDeviceand keeps its own fake identity). Smoke-checked: identity resolves, discovery raises cleanly with no hardware, debug device initializes.testMillennia.py: 14 passed, 6 skipped.🤖 Generated with Claude Code