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# NACK

### ID: 2

### Payload Definition

<table><thead><tr><th width="191">Data Type</th><th width="219">Name</th><th>Description</th></tr></thead><tbody><tr><td>u16</td><td>id</td><td>id of packet being nack'd</td></tr><tr><td>char[]</td><td>error msg</td><td>optional ascii string describing error. need not be null terminated. length is discerned from packet payload length field.</td></tr></tbody></table>