| 摘要 |
A cable television converter with remotely modifiable functionality receives firmware downloaded over a cable television network. The integrity of the firmware is verfied and if valid, the firmware is executed to provide one or more converter funtions. If the firmware is invalid, default operation software contained in ROM is executed instead of the firmware to return the converter to baseline operation. In one embodiment, the converter includes a frequency agile data receiver to receive control instructions on a first data channel and firmware on a second data channel. The receiver is forced back to the first channel if a successful firmware download does not occur on the second channel within a predetermined time period. The firmware is continuously transmitted in short segments, and the converter can continue to receive segments until all the segments of a designated firmware package have been successfully downloaded, unless the predetermined time limit expires sooner. |
