r8n
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Paste your AT log.
Get a diagnosis in seconds.

r8n analyzes modem AT command logs and tells you exactly why your IoT device won't connect — registration denial, APN mismatch, signal issues, band lock, PIN lock, and more.

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What r8n diagnoses

13 detection rules covering the most common cellular IoT failure modes.

Registration denied
SIM not yet propagated to carrier HSS, or barred on this network.
Wrong APN
PDP context won't activate because the APN string is incorrect.
Marginal signal
RSRP / RSSI near the sensitivity floor — intermittent drops expected.
Band lock
Modem locked to a band with no coverage at the deployment site.
SIM PIN locked
Modem halted waiting for PIN; device firmware doesn't enter it.
PSM too aggressive
Power-saving mode keeps the modem unreachable for too long.
Roaming denied
Carrier policy blocks data in this country or on this PLMN.
SIM not detected
CPIN/CCID errors — physical SIM contact or provisioning issue.
eUICC fallback failure
Profile switch didn't trigger despite the signal threshold being crossed.
DNS failure
PDP context up but DNS resolution failing — data path issue.
Quota exhausted
Data cap hit; SIM is live but all traffic is blocked.
Modem unresponsive
AT interface not responding — firmware hang or hardware fault.
Healthy baseline
Everything looks normal — confirms the log is clean.

How it works

1
Paste your AT log
Copy the raw modem transcript from your serial console, UART capture, or SDK log output.
2
Get an instant diagnosis
r8n identifies the fault, surfaces the exact evidence lines, and ranks hypotheses by confidence.
3
Get a draft fix
A ready-to-send customer reply and next-action checklist come with every diagnosis. Copy and go.

Works with any cellular modem

r8n is vendor-agnostic. It recognizes logs from all major module families.

Quectel BG96/BG95/EC25 u-blox SARA-R4/R5/R6 SIMCom SIM7080G/SIM800 Telit ME910 / LE910 Sierra HL7800 Nordic nRF9160 Any AT-compatible modem

Ready to diagnose?

No account. No API key. Paste a log and go.

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