Skip to content

docs: HRM 200 pairing and trainer dropout notes #3

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
rlfleming93 merged 1 commit into from
Oct 20, 2026
Merged

docs: HRM 200 pairing and trainer dropout notes #3

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
3 changes: 2 additions & 1 deletion docs/ble-protocol.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -117,7 +117,7 @@ Worked: `16 96 20 03` = 150 bpm, contact, RR 800/1024 s.
|---|---|---|---|
| HRM-Pro / Pro Plus | Yes | 2 | + unlimited ANT+; watch coexists |
| HRM-Dual | Yes | treat as 1 | watch on ANT+ if worn |
| HRM 200 | Yes | — | must be in **Open** (not Secure) pairing mode |
| HRM 200 | Yes | — | must be in **Open** (not Secure) pairing mode. Observed 2026-10: first connect from a Mac fails with SMP Pairing Failed reason 5 (Pairing Not Supported) and the link drops; hold the button 4 s (pairing mode, 5 min) and the next attempt bonds. The bond persists; later connects need no button |
| HRM-Run/Tri/Swim | **No** | — | ANT+-only, invisible to Mac |

## ERG loop practice
Expand All @@ -127,3 +127,4 @@ Worked: `16 96 20 03` = 150 bpm, contact, RR 800/1024 s.
- Death spiral: trainer physics, not protocol. App guard: cadence < 40 rpm for 5 s ⇒ temporarily drop target to 50 % FTP; restore at ≥ 60 rpm.
- One gear, no shifting in ERG (Cog makes this moot).
- If CP writes fail with insufficient auth/encryption: bond (spec lists Encryption on 0x2AD9); macOS just-works LE usually suffices.
- Dropout: when the trainer link drops or Indoor Bike Data goes stale (> max(3 ticks, 3 s)), the engine pauses the rider (`pauseReason: 'trainer'`) instead of recording 0 W, and resumes on the next fresh sample, re-sending the ERG target.
Loading