# USB09 isolated 32 KiB independent Pi pass

Status: complete
Type: evidence
Updated: 2026-08-01
Next Action: none; the complete broad-matrix sequence passed

Project Map: work/maps/map-smi-firmware-stabilization-and-qualification.md
Workpackage: work/wp/completed/wp-restore-broad-usb-compatibility-baseline.md
Checklist: work/checklists/checklist-stage-1b-four-drive-usb-compatibility-baseline.md
Incident: work/incidents/incident-usb09-false-write-failure-and-usb-compatibility-architecture-correction.md

## Exact identity and state

The Pi identified the same newly formatted USB09 after Controller A use:

- label `USB09`, UUID `50D2-5C43`;
- DOS partition-table identifier `0x9d4ee4ca`;
- General UDisk serial `2512300955508200677718`;
- model/revision `UDisk / 5.00`, ANSI level 2;
- 15,728,640 logical blocks at 512 bytes, totaling 8,053,063,680 bytes;
- one FAT32 LBA partition from sector 32 through sector 15,728,639;
- unmounted before and after every check.

## No-repair filesystem gate

- `fsck.fat -n -v` reached the final filesystem sector, found two FATs, and
  reported 5 files using 18 of 245,631 data clusters. It found no structural
  corruption and left the filesystem unchanged.
- Exit status 1 is solely the known Windows label convention: label `USB09`
  exists in the root directory while the boot-sector label remains blank.
- FAT1 and FAT2 are byte-identical. Each 983,040-byte FAT hashes to
  `E8491713D94571E5CB6DBD0065D91EDFFCFE698E667E736E2089E70F2AB4FFA1`.
- No `HPTE.TMP`, `.tmp`, `.part`, `.bak`, or unexpected controller artifact
  exists.

## Exact publication gate

| Gate | Result |
| --- | --- |
| Filename | `USB09_32K.csv` |
| Bytes | 429,175, exact controller count |
| SHA-256 | `FEE59B4062224EAB0BD30A2B44EA5EDDEE56623B3B3205BC7228B35BD4FB0D34` |
| Total lines | 8,558 |
| Data records | 8,540 |
| CSV line sequence | 1 through 8,540, zero mismatches |
| Requested HPT range | `301739760` through `302268900` |
| Actual HPT range | `301739760` through `302268900` |
| Actual HPT sequence | 2 through 8,541 |
| Health metadata | 8,540 healthy, 0 degraded, 0 snapshot/request gaps |
| Snapshot validation | `COMPLETE` |
| Final marker | `Export completion: COMPLETE; records published: 8540` |

The controller-side and Pi-observed byte counts match exactly. The CSV contains
all selected records in order and is independently readable through its final
completion marker.

## Transport and final state

The current Pi insertion logged normal USB/SCSI enumeration and no USB reset,
timeout, medium error, device-offline, buffer-I/O, or block-I/O error. USB09 is
unmounted and left unchanged after read-only inspection.

Raw evidence remains under the ignored directory:

`work/evidence/generated/usb09-32k-recovery-pi-verification-20260731/`

## Disposition

USB09's isolated 32 KiB incident regression passes end to end. The candidate
eliminates the repeated 1 KiB close-timeout failure without a drive rule,
transport fork, retry/replay, optional SCSI durability command, VBUS action,
or controller power action. USB09 is resolved as a required specimen, but
broad compatibility remains blocked on the identical four-drive A/B matrix.
