| Parameter | Description | 
| entry | An entry to be added to the history. | 
| timestamps | Index for an add, clear or retrieve operation. | 
| most recent first | Set to true to order the history so that the most recent element is first, false for least recent first. | 
| max size | Maximum number of entries to retain - set to 0 to retain all entries. | 
| delimiter | String to separate history entries when output by the block. If not specified, the default is "\n" (linefeed). | 
| time format | String format to display time-stamps, if required. A default format is used if this is not set. | 
| Operation | Description | 
| add | Adds the content of entry to the history - an output update will automatically be produced. | 
| clear | Clears the history. | 
| retrieve | Causes the latest history to be output from the block as a single, delimiter-separated string. | 
| Feed | Field | Description | 
| history | size | Number of entries in the history. | 
| text | Text representation of the history, where each entry is optionally time-stamped and separated by the delimiter string. |