To install a different version software into an HP dimmer the following equipment is needed:
1. DOS Computer with either COM1 available. The computer must support COM speeds of 19200 Baud - note some laptops do not support this rate.
2. Download cable
3. HP dimmer software disk
4. Blank Floppy Disk

To update the software:
1. Copy the download files from the software diskette onto the computer hard disk.
2. Switch the dimmer off.
3. Using the download cable plug the serial output of the computer into the DMX input of the HPTR to be updated.
4. Press and hold the "Enter" button on the HP dimmer while turning dimmer power on. The dimmer display will show "LOAD".
5. Open an MS-DOS prompt, and change to the directory where the files were copied.
6. Start the download by typing "Download xxx<ENTER where xxx is the filename of the software to be downloaded eg hp2_2. The dimmer display will show "DATA" and the keypad LEDs will flash in sequence as the data is transferred. The transfer takes approximately 30 seconds.
7. At the completion of the download the dimmer will blank its display and program the data to the internal FLASH device.
8. When the display reactivates, switch the dimmer off.
9. Deep clear the dimmer by holding down the "Mode" and "DMX Bank" buttons while turning power on.
10. Select "240V" and press "Enter".
11. Select "12Ch" and press "Enter".
12. Check dimmer software has been correctly loaded by pressing and holding the "Enter" button. After about a second the display will show the version number ie 2.2 etc.