# Error Codes & Security (S16-S17)

## §16 — Error codes

XPOS ESDC returns only the prescribed FRCS error codes; any manufacturer-specific message is listed in the User Manual. Representative mappings:

<table id="bkmrk-codemeaning-1300no-c"><thead><tr><th>Code</th><th>Meaning</th></tr></thead><tbody><tr><td>1300</td><td>No card / Secure Element not present</td></tr><tr><td>1500</td><td>PIN required</td></tr><tr><td>2100 / 2110</td><td>PIN incorrect / attempts remaining</td></tr><tr><td>2210</td><td>Secure Element limit reached — audit required</td></tr><tr><td>6308</td><td>Certificate not valid for the current date</td></tr></tbody></table>

## §17 — Security &amp; prohibited functions

- **PIN handling** — the PIN is held only in working memory and is cleared on restart; it must be re-entered after any restart.
- **Fixed protocol** — the POS-to-SDC contract and its parameters are not user-editable.
- **Label enforcement** — invoices with labels outside the active tax group are rejected.
- **Prescribed responses only** — no non-standard error responses are emitted.
- **Fiscal integrity** — signing and counters are performed solely on the SE; XPOS ESDC cannot alter fiscal data or reset counters without a valid proof-of-audit.